DATE DUE
NOV 37 19^
^
Arrt -to . .
I
WHY WE BEHAVE
LIKE HUMAN BEINGS
HARPER'S
MODERN SCIENCE
SERIES
Sir William Bragg, K.B.E., D.Sc..f.r.s.
Concerning the Nature of Things
Richard Swann Lull, Ph.D., D.Sc.
Professor of Paleontology, Y»Ic University; Director,
Peabody Museum; Fellow of the American Academy
of Arts and Sciences, etc.
The Ways of Life
George A. Dorsey, ll.d., Ph.D.
Formerly Curator of Anthropology, Field Museum,
and Associate Professor of Anthropology, University
of Chicago.
Why We Behave Like Human Beings
Bertrand Russell
The A B C of Relativity
IN PREPARATION
Edwin Grant Conklin, Ph.D., Sc.D.
Professor of Bio lo5y, Princeton University ; Fellow of
the American Academy of Arts and Sciences, etc.
The Revolt Against Darwinism
Charles Singer, D.Litt., M.D., F.R.C.P., f.s.a.
Late University Lecturer in History of Biological
Sciences. Oxford.
History of Science
HARPER er BROTHERS
PUBLISHERS
HARPER'S MODERN SCIENCE SERIES
WHY WE BEHAVE
LIKE HUMAN BEINGS
BY
George A. Dorsey, Ph.D., LL.D
Formerly Associate Professor of Anthropology
University of ChicagOy and
Curator of Anthropology
Field Museum of Natural History
Publishers
Harper & Brothers
New York and London
1925
WHY WE BEHAVE LIKE
HUMAN BEINGS
Copyright, 1925, by
Harper & Brothers
Printed in the U. S. A.
First Edition
H-Z
TO
Father and Mother
Digitized by the Internet Archive
in 2014
https://archive.org/details/whywebehavelikehOOdors_0
CONTENTS
Preface xi
Chapter I. The Individual Life Cycle and the Human Race
1. The Egg of Life 1
2. The Embryonic Germ-Layers 3
3. The Fetal Gill-Clefts 6
4. The Fetal Nervous System 9
5. The Fetal Skin and Sense Organs 12
6. The Fetal Urogenital System 16
7. The Fetal Alimentary Canal 19
8. Twins and Monsters 22
9. Walking Museums of Anatomy 25
10. The Maturing Body 32
IL The Adult and Senile Body 34
12. The Human Race 38
13. The Two Great Divisions of Man 44
14. Fossil Man 47
15. Our Next-of-Kin-Living 49
16. Changing Limbs 53
17. The Race to Be Human . 56
Chapter H. The Evolution of the Earth, Life, and Sex
1. Life's Genealogic Timetable 60
2. The Hand That Rocks the Cradle
3. Experiments in Brains 69
4. New Styles in Eggs and Incubators 71
5. Our Indebtedness to Fish 73
6. Back to the Lifeless Earth 77
7. The Start from the Sun 80
8. The L M N's of Nature 82
9. The Fitness of Water and Carbon Dioxide ...... 86
10. The Evolution of the Organic . v . U . 92
vii
CONTENTS
11. Darwin and Natural Selection 97
12. Lamarck and Acquired Characters 102
13. The Nature and Evolution of Sex 105
14. The Colored Bodies of the Egg 110
15. The Great Game of Heredity 112
16. Eugenics, or Being Well Bred 116
Chapter III. The Processes of Living and the
Germs of Disease
1. Life Is Change and Requires Energy 120
2. The Body is a Living Machine 123
3. It Requires Calories 127
4. Why We Must Digest Food 130
5. The Digestive System 133
6. Our Daily Bread and Water 137
7. Seeing Food Through the Canal 146
8. How Food is Absorbed 154
9. The Flesh Is in the Blood 159
10. How the "Flesh" Is Transported 164
11. Giving the Blood the Air 167
12. The Great Blood Purifier 170
13. The Red Blood-Cells 173
14. The Body Thermostat 177
15. The Role of the Duct Glands 183
16. The "Little Fleas" 186
17. The Deadly Germs 194
Chapter IV. The Endocrine Glands and the Causes
of Death
1. Endocrine Glands and Hormones 201
2. The Thyroid Gland 204
3. The Parathyroid and Thymus Glands 206
4. The Adrenal Glands 208
5. The Emergency Functions of the Adrenals 212
6. The Pituitary and Pineal Glands 215
7. The Pancreas— and Other "Sweetbreads" 219
8. Introducing the Gonads 221
9. The Dual Role of the Gonads 224
10. The Female Gonads 226
U. The Male Gonads 229
yiii
CONTENTS
12. Secondary Sexual Characters 232
13. The More "Human" Sex 235
14. Endocrine Facts and Fancies 238
15. The Individual That Is Regulated 240
16. "How Can a Man Be Born When He Is Old?" 243
17. One Good Defect Deserves Another 248
18. The Parts That Wear Out First 251
19. The Best Life Insurance 254
20. Our Total Mileage 257
Chapter V. The Integrating Organ and Mechanism
OF Adjustment
1. The Old and the New Psychology 263
2. The Impulse to Live 266
3. Samples of Low Life Behavior 268
4. The Animal "Mind" 270
5. The Excitability of Living Matter 274
6. The Nature of the Reflex Arc 278
7. The "All-or-None" Conductors 281
8. Reflex Action 284
9. The Nature of Nerves 287
10. The World as Stimulus 291
11. Receptors of Sights and Sounds 294
12. Receptors of Chemical Stimuli 298
13. Visceral and Kinesthetic Receptors 301
14. The Nervous System 306
15. The Lower Centers of the Nervous System 309
16. The Supreme Adjustor 312
17. The Pictured Movements of the Brain 315
18. The Conditioned Reflex 319
19. The Autonomic Nervous System 321
20. Cramps and Fatigue . 325
21. Mind and Consciousness 328
Chapter VI. Acquiring Human Behavior
1. A Stork's-eye View of the Baby 336
2. Instinctive Behavior 340
3. Organizing the Kinesthetic Sense 345
4. The Reflex Basis of Habits 349
5. Play and Imitation 353
ix
CONTENTS
6. The Laws of Habit Formation 356
7. Instinctive Emergency Behavior 359
8. The Fear-Hate Organization 363
9. Childhood's "Unconscious" Mind 368
10. The Habit of Language 372
11. Verbalized Organization 377
12. Adjustment by Thought and by Words ....... 381
13. Learning and Remembering 385
14. The Changing Situation 388
15. Positive and Negative Adaptations 391
16. How Habits Are Broken 393
17. The Habit of Sleep 396
18. "Prophecy lies in ... 'I have dreamed' " 400
19. Learning to Know 403
20. Knowing and Believing 408
21. The Individuality of Response 412
Chapter VII. From the Standpoint of the Newer
Psychology
1. Instinctive Activities 416
2. The Hunger Complex 420
3. The Complex Appetite 424
4. The Sex's Complex 427
5. Love's Coming-of-Age 431
6. Bisexual Behavior 435
7. Conditioning the Sex Complex 438
8. Marriage Behavior 441
9. Freud's Devil and Other Psychoses 447
10. Fake Psychology 452
11. Reading the Mind 455
12. Measuring Intelligence 458
13. Character and Personality 461
14. The Ideal in Human Behavior 464
15. Socially Useful Behavior 471
16. The Goal of Creative Evolution 477
Bibliography 485
Index 489
X
PREFACE
TTUMAN beings are the most interesting objects on earth,
and to know themselves and get along with one another
is their most important business. That business drags
because they do not know where they come from, how
they get here, what they bring with them, what they do with
it, and what they could do if they stopped quarreling among
themselves and used their brains to solve their common
problems. It will speed up when the raw materials of human
nature and the possibilities of intelligent behavior are more
generally understood. The facts for such an understanding
are known, but they belong to several sciences and are scat-
tered through many libraries. To pick them out, put them in
order, and make them tell a complete and up-to-date story
that can be held in one hand and read without a dictionary
is the object of Why We Behave Like Human Beings.
"Complete" is a large word and must be taken with a grain
of salt. Nothing is really complete in this world of ceaseless
change and expanding horizon. The earth itself is not the
earth it used to be when I first went to school. Man's story
will be complete when there is no human being left to tell
the tale. Keibel and Mall's Human Embryology, with 1,600
pages, is more complete than Minot's, with only 800.
Quain's Human Anatomy, with 2,000 pages, is more complete
than the average textbook of anatomy, with only 1,000.
This is not a textbook; the changing human body, from a
rejuvenated ovum to senile decay, and its origin from
primordial protoplasm, are part of this story.
Nor is "up-to-date" to be taken too literally. Science moves
fast these days. I may state that the hormone of a certain
xi
PREFACE
gland is "not yet known"; Professor John Abel may have
isolated it yesterday and announce the fact next year. When
I studied anatomy under Thomas Dwight — ^to whom I owe
much — I was told nothing about a certain little gland in our
throat without which we cannot live. The activating principle
of that gland has been discovered, and the secretion of an-
other vital gland has been isolated, since I wrote the first
word of this book. No one had heard of a vitamin a few
years ago, nor had any vitamin been isolated when I began
this book; one, and possibly two, has since been isolated.
By "complete" I mean comprehensive. This is the most
comprehensive account of human beings that I know of.
It is as up-to-date as I can make it. It moves as fast as I
can make it, and avoids blind alleys which lead nowhere.
It does touch many problems not yet solved or only partially
guessed at; its handling of such problems is as sound and
sane as I can make it with the help of many friends. This
does not commit them for my errors of omission and com-
mission, nor lessen my responsibility for statements of fact
or inferences from facts and hypotheses — nor signify that
they approve an anthropologist's use of their materials for
his story.
The paleontologist, for example, claims fossils. But when
he finds a skull which he says belonged to an ape-man or
to a man-ape, that skull belongs to me also; when he finds a
set of dinosaur eggs, I am not interested: there are no dino-
saurs in our family album. The bacteriologist and a dozen
other 'ologists, as well as the family doctor and dentist, deal
in bacteria; as do I also, in setting forth the role these
amazing little imps have played in organic evolution and in
the life and death of human beings. The physiologist — and
presumably every scientist — is interested in the news about
the endocrine glands. The news is startling; but much that
is not yet known or is known to be false has been so capital-
ized by quacks and marvelmongers that I have tried to sepa-
rate the glands from the grafters. Different scientists
xii
PREFACE
specialize in psychic behavior. Psychics and pseudo-psy-
chologists exploit it; they too belong to the story of why
we're human. In short, my attitude is that any science which
holds itself aloof from life and nowhere comes in contact
with human beings is as barren as a Vestal Virgin and as dry
as a prayer for rain for the purpose of this book; but that
the scandalmongers of science who would fill their lamps at
the expense of the gullible, and who illumine no path of life
nor sustain any living germ, should be illuminated.
This book does not presume to offer a Philosophy of Life
or suggest Science as a substitute for Religion. But as
philosophy was moonshine until it began to investigate the
elementary properties of matter and energy, so, I suspect,
religion will be subject to quackery and hypocrisy until
humanity itself becomes more humane than human nature
and religion itself ceases worrying about heaven and hell
and devotes its energies to making this earth a paradise.
* Nor, in ascribing "mind" to a specific irritability of proto-
plasm and human actions to definite forms of energy, does
this book pretend to "resolve life." Life is more easily
destroyed than resolved, or even defined. Nobody knows
what life is. Much is known of living processes. Of the
electric change accompanying irritability, of the action of
X-rays on living protoplasm and of heat, light, and sound
waves on sensitive human bodies, not much is yet known.
But those energies and the living mechanisms which react
to their stimuli can be investigated. The few crumbs that
science can offer are more nourishing than the no-bread
of speculation which works without oxygen, ignores carbon-
compounds, and defies the lightning.
Parts of the chapter on the "Processes of Living" will be
difficult for those unfamiliar with H2O and CO2. Some may
even sympathize with the French Republic of 1794 for having
beheaded the man who said that life is a chemical function.
But Lavoisier was right: life is a chemical function — and
xiii
PREFACE
living actions are largely concerned with conjugating the
verb to eat. Without some idea of oxidation processes, of
the chemical structure of food, and of the chemical reactions
in digestion, visceral behavior is a blank. And without some
understanding of visceral behavior, psychic behavior is up
in the air. Life became a science when interest shifted
from the dissection of dead bodies to the study of action in
living beings and the nature of the environment they live in.
To those scientists who have given me of their time and
learning I am profoundly indebted and here offer my grate-
ful thanks: to Dr. W. I. Thomas, who read the entire MS.;
to Dr. Adolph H. Schultz, of the Carnegie Institution of
Washington, Department of Embryology, Johns Hopkins Uni-
versity, who read Chapter I; to Professor Franz Boas, of
Columbia University, who read parts of Chapter I; to Pro-
fessor George Grant MacCurdy, of Yale University, who
read parts of Chapters I and II; to Professor W. E. Castle,
of Harvard University, who read Chapter II; to Professor
Richard Swan Lull, of Yale University, who read Chapter II
and parts of Chapter I; to Professor Walter B. Cannon, of
Harvard University, who read part of Chapter III; to Dr.
McKeen Cattell, of the Cornell University Medical School,
who read Chapter III; to Professor A. J. Carlson, of the
University of Chicago, who read Chapter IV; to Professor
C. Judson Herrick, of the University of Chicago, who read
Chapter V; and to Dr. John B. Watson, who read Chapters VI
and VII.
I am also indebted to Professor Carlson for the privilege
of examining, while in proof, his chapter on Organotliera-
peutics in the Blumer edition of Billings-Forchheimer's
Therapeusis of Internal Diseases; and to Professor John J.
Abel of Johns Hopkins University, Professor R. G. Hoskins
of the Ohio State University, Dr. C. R. Moore of the Univer-
sity of Chicago, and Dr. John B. Watson, for reprints of
articles and for valued suggestions.
xiv
PREFACE
Two names I wish especially to mention: Professor Franz
Boas, unfailing source of inspiration to all American an-
thropologists; my wife Sue, untiring and indispensable ally
in all that has gone into the writing of this book.
George A. Dorse y.
New York City, June 1, 1925.
XV
WHY WE BEHAVE
LIKE HUMAN BEINGS
eine Arbeit wird eigentlich nie fertig"
Goethe
CHAPTER I
THE INDIVIDUAL LIFE CYCLE AND THE HUMAN RACE
1. The Egg of Life. 2. The Embryonic Germ-Layers. 3. The Fetal Gill-
Clefts. 4. The Fetal Nervous System. 5. The Fetal Skin and Sense Organs.
6. The Fetal Urogenital System. 7. The Fetal Alimentary Canal. 8. Twins
and Monsters. 9. Walking Museums of Anatomy. 10. The Maturing Body.
77. The Adult and Senile Body. 12. The Human Race. 13. The Two Great
Divisions of Man. 14. Fossil Man. 15. Our Next-of-Kin-Living. 76. Changing
Limbs. 77. The Race to Be Humane.
1
We know of only three kinds of living beings: bacteria,
plants, animals. All living beings have a physical body or
structure made up of a few of the more common chemical
elements. This body is called protoplasm, the stuff of all
living things. Living protoplasm occurs only in units called
cells. Every living being is or has been a cell. Cells are
always small and generally cannot be seen except under the
microscope.
Many animals consist of just one cell, and hence are
called unicellular organisms. Yet that cell suffices for them
to live; they eat, they excrete, they grow, they multiply;
they obey all the laws of living organisms. For living pur-
poses they are complete. Higher animals have bodies of
many cells, and are called Metazoa to distinguish them from
the Protozoa, or unicellular animals.
We are animals and belong to the Metazoa group. Our
body consists of about twenty-six thousand billion cells.
Each cell is alive and must be nourished or it dies.
The cells which make up our body are of diflferent forms
and shapes and, except the free floating cells carried by the
1
WHY WE BEHAVE LIKE HUMAN BEINGS
blood, are united into different kinds of tissue to form the
organs and systems of our body. But a section cut anywhere
from the body — from bone, muscle, eye, tongue, skin, heart —
would under the microscope be seen to consist of tiny cells,
each a complete unit of protoplasm.
Our body begins its individual growth and development as
one cell, the germ-cell or fertilized ovum (egg). By fer-
tilization, the ovum, an old cell, is stimulated to begin a new
life; it is made young again. Being rejuvenated, it can grow,
and grow old.
The germ-cells (female, or ova; male, or spermia) are
readily distinguishable under the microscope. Ova are much
larger and less active than spermia. The latter are very
active, and propel themselves by a whip-lash tail. Both are
complete living organisms and in their combined bodies
carry immortality. In general features, size, structure, etc.,
human germ-cells closely resemble those of other mammals.
The human ovum was first discovered in 1827. Although
it is the largest of the cells in the body, fifty thousand could
be mailed across the continent for a two-cent stamp; one
hundred could ride on an inch-long spider web.
In both sexes, the germ-cells mature normally only from
the beginning of puberty. The ova develop in little pockets
or follicles of the ovaries. There are about 70,000 follicles
at birth. By the eighth year there are less than 40,000; of
these only about 200 develop into true Graafian follicles.
One of these, containing a single ovum, matures each lunar
month of life between puberty and the menopause. It es-
capes through the ruptured wall of the ovary and enters the
Fallopian tube, presumably two weeks before the onset of
menstruation. For each mature ovum thus released each
lunar month, the male develops about 850,000,000,000
spermia.
One spermium only enters into the body of the matured
ovum, leaving its tail outside. The ovum is now fertilized.
It divides into two cells; these two divide and become four,
2
THE LIFE CYCLE AND THE HUMAN RACE
etc. In nine months, one fertilized ovum has grown five
million per cent and increased in volume one billion times;
by maturity it will have increased in volume fifteen billion
times.
After the fertilized ovum has by division become many
thousands, certain cells under the microscope may be dis-
tinguished from the others. These are to become the germ-
cells of new individuals, tiny sparks of immortality, endowed
with the capacity to hand life on to the next generation.
The other cells of the tiny embryo are called soma, or
body cells. They also grow and multiply by division, and
assume special shapes to fit them to form the tissues and
organs of the body — nerves, eyes, bone, teeth, heart, muscle,
blood, etc. Having specialized or become differentiated,
they cannot unite with other cells to start new lives — they are
not germ-cells.
2
We hear much of adaptations. Every living animal is
"adapted" or it could not live. What it is adapted to and
what it adapts itself with depend on the animal and the
stage of its development. The tiny germ-cell in the hen's
egg is adapted to an environment of yolk and albumin. It
draws on these for its nourishment. The human ovum has
no such store of food to draw upon. It is adapted to a
different environment. For 280 days it is to live the life of
a true parasite. It must therefore attach itself to a living
wall, from which it can derive its supplies for living and
for growth. These early adaptations of the human ovum are
of great interest.
But the interest will be increased if we have before us a
law of biology which says that individual development re-
hearses or recapitulates the life history of the species. This
means that our individual prenatal and postnatal growth up
to the time of adolescence is a resume of the evolution of the
3
WHY WE BEHAVE LIKE HUMAN BEINGS
human race. It does not mean that at one stage of develop-
ment the fetus is a fish, or a reptile; it does say that the
ovum develops along the road our ancestors traveled in
becoming human.
We begin our individual existence as a protozoon or single-
celled animal; not until the end of the third month has the
fetus the essential parts of a fairly complete human being.
During the last six months the fetus grows more human; the
parts begin to mature, and for years after birth keep on
maturing.
The embryo begins at once to develop from its own body
the two fetal membranes or envelopes. The inner one, or
amnion (lamb), fills with a pint or more of water. In this
the embryo floats, and consequently any pressure to which
it is subjected becomes more evenly distributed. By a special
growth called placenta (cake, because of its shape) of the
outer membrane or chorion (skin), the embryo attaches itself
to the wall of the uterus.
Through this placenta the parasite embryo derives food
and oxygen. But it develops its own blood and its own,
circulatory and digestive systems: they are at all times quite
distinct from its host's. She supplies what the chick embryo
receives from the hen egg: support, protection, water, food,
fuel, oxygen.
Both fetal membranes and placenta follow the child at
birth. The child is freed from the placenta by severing its
umbilical cord ; our navel is the scar.
In other mammals these membranes are not formed so
early, but the upright gait of man seems to put more strain
on the abdominal viscera and presumably subjects the embryo
to greater pressure. It needs all the protection it can get,
hence this marvelous intrauterine adaptation to the upright
posture. Anthropoid apes have the human type of uterus and
a near-upright gait; their fetal membranes are also formed
earlier than in other mammals.
To return to the embryo proper. The ovum divides, tlie
4
THE LIFE CYCLE AND THE HUMAN RACE
two daughter-cells divide. Four, eight, sixteen, thirty-two,
etc. As a result of this rapid division, multiplication, and
growth, the embryo passes through certain definite stages of
development. Much is still conjecture. For this reason:
The earliest stages of embryonic development of fishes, am-
phibians, birds, and of such domesticated mammals as the
guinea-pig, rabbit, sheep, and pig are known, and much may
be inferred as to the course of development of the human
embryo from what is known to take place in these animals.
But no one has yet seen a fertilized human ovum, nor has
anyone yet seen a human embryo that had not already had
ten days' growth — and it measured about one one-hundredth
of an inch in length. Even of the second week of human
development almost nothing is definitely known, and of em-
bryos of the third week the Carnegie Laboratory of Embry-
ology has been able to assemble only fourteen specimens.
What actually goes on, then, during the first eighteen days of
man's intrauterine existence can as yet only be inferred from
known facts of lower mammalian embryonic development.
First of the hypothetical stages is the morula (little mul-
berry) : the embryo is a minute cluster of cells. Next is the
blastula stage, or blastoderm (germ-skin) ; the embryo is
supposed to form a hollow sphere. This caves in on one side,
forming a U-shaped affair, and represents the gastrula
(stomach) stage. By this infolding, certain cells which were
on the outside now lie inside the body; the embryo consists
of two layers. By further infoldings, there is an additional
layer between these two. Thus we have the famous and
important germ-layers: the outer or ectoderm; the inner or
endoderm; the middle or mesoderm.
Each germ-layer gives rise to certain organs and systems,
a fact of far-reaching consequence in medicine and hygiene
and in an understanding of our body. The three layers and
their derived structures are:
L Ectoderm: skin and skin accessories; entire nervous
5
WHY WE BEHAVE LIKE HUMAN BEINGS
system; special sense organs; pineal gland and part of the
pituitary and adrenal glands.
II. Endoderm: alimentary canal and appendages; thy-
roid and thymus glands ; larynx, trachea, and lungs.
III. Mesoderm: voluntary or skeletal muscles; urogenital
system and sex glands; part of the adrenal glands.
In addition to these three layers, a particular type of tissue
develops, chiefly from the mesoderm. Its cells are branched
and form a network of connective tissue. From it are de-
rived the heart, blood, blood vessels, and lymphatic system;
skeleton ; and visceral or involuntary muscles.
All one-cell animals consist of an outside and "insides."
Through their outside membrane or cell wall they keep in
touch with the world. Our keep-in-touch-with-the-world
mechanisms (skin, hair, nails, all skin-glands and organs,
lining of mouth, enamel of teeth, special sense organs, and
entire nervous system) are all derived from the outside cells
of the original hollow body when it caved in to bury certain
cells inside the body. From those inside cells we develop
"insides" — food and air canals. Muscles and skeleton,
blood, sex organs, etc., did not appear until animal life had
made much progress in evolution.
During our early prenatal days we live fast; we can be
certain of that. In a few days we have developed structures
^that were evolved only after tens of millions of years. ,
3
Within two weeks the embryo has become a minute plate-
like structure with a streak across it. By the third week this
streak opens into the plate at both ends. One opening
becomes the mouth. The cavity within the embryo will
divide and become the thoracic and abdominal cavities.
Meanwhile, a series of lines appear, dividing the plate-like
embryo into segments. Segmented animals, such as worms
and insects, retain these segments; as do fishes in muscles,
6
THE LIFE CYCLE AND THE HUMAN RACE
ribs, and vertebrae; as do we in our ribs, vertebrae, and the
muscles between the ribs. Our floating ribs are simply in-
complete ribs, but we have vestiges of ribs all the way down
our spine. Those below the chest fuse with outgrowths
from die vertebrae and are called lateral processes.
The vast majority of animals have no backbone, and are
called Invertebrates. One of the greatest steps in evolution
was a backbone or vertebral column. Three types were tried
out before Vertebrates developed a true backbone. All three
types or stages appear in the developing human embryo. The
notochord or permanent body axis of the lowest fishes appears
early; later it is obliterated by the bodies of the vertebrae,
but traces of the notochord may persist and lead to tumors
in adult life. Our bony vertebrae proper are preceded by
cartilage, the only backbone sharks have. This is replaced
by bone.
Our skull and limb bones also begin as cartilage — and in
some fishes the skull remains cartilage. Much of our long
bones and skull is still cartilage at birth; hence the pliancy
of the new horn's head.
Shark embryos have five gill-arches with openings, or gill-
clefts, between, and two branchial arches from which the
shark forms its poorly developed lower jaw.
Most of these arches and the branchial clefts between
appear at the third week in the human fetus. The way the
clefts disappear and the arches develop into the extraordi-
narily complicated human throat is possibly the most
interesting and confused chapter in human embryology.
From one of the two arches which develop into jaws in
sharks, the human fetus develops its lower jaw and two of
the three tiny bones of the inner ear; from the other arch, the
third bone of the inner ear, the styloid process at the base
of the skull, and the cartilage of the external ear. The
hyoid apparatus which supports our tongue develops also
from this and from the first gill-arch. The second and third
7
WHY WE BEHAVE LIKE HUMAN BEINGS
gill-arches become the thyroid cartilages, or Adam's apple;
the fourth, the epiglottis; the fifth, the windpipe cartilages.
As the human embryo will develop into a lung-breather
and will have no need of gills, the gill-clefts do not break
through; after the sixth week no outward trace of them
remains. But around one end of the first cleft the fetal ear
develops; the remainder becomes the Eustachian tube, or
passage from the mouth to the tympanic cavity of the ear.
The second branchial arch, from which fish embryos de-
velop gill-cover and gill muscles, is supplied by the seventh
cranial nerve. This arch in the human fetus is also supplied
by that nerve; it grows upward and becomes the great nerve
of our face, supplying ears, mouth, nose, and eyes. An
amazing story, this. The nerves of our face moved the
gill-covers of our respiratory system when we were fishes.
Six branches of the aorta — the great artery from the
heart — supply these fish-like arches of the human fetus.
The third pair become part of the two internal carotid
arteries. The left branch of the fourth pair forms the bend
of the aorta. Of the sixth pair, one part becomes the stem
of the pulmonary artery; the other, during fetal life, carries
blood from the pulmonary artery to the aorta, thus permitting
the right ventricle of the heart to pump impure blood into
the aorta and so to the placenta. At birth it closes; blood
from the pulmonary artery must now pass to the lungs.
Marvelous adaptation! Part of a gill-arch artery used for
placental circulation closed suddenly to meet the infant's
cry for air! Henceforth the infant gets oxygen from its own
lungs and not from its mother's blood.
During fetal life, the third and fourth clefts become cov-
ered by a fold from the second arch. A fistula may develop
here — remnant of an enclosed gill chamber. The middle ear,
site of the first fetal gill-cleft, is more prone to serious
trouble. Tags of skin which may persist on the side or front
of our neck are less serious, but none the less echoes of our
gill-clefts, reminders of our kinship with the finny tribes.
8
THE LIFE CYCLE AND THE HUMAN RACE
At the time the gill-clefts are present the human fetus has
a freely projecting tail and four tiny paddle-like limbs.
4
The ovum only grows and develops if it can come in contact
with food; the cells remain alive only as long as they are
nourished. This gives us a clue to some of the mechanisms or
organ-systems which the human embryo must develop and
which we must keep in repair during life. Whether we are
a one-cell embryo or a new-born or an adult, we must be
able to get food and oxygen and distribute food and oxygen
where needed. We have such organ-systems: digestive, cir-
culatory, respiratory, etc.; and a motor mechanism of bones
and muscles.
A fundamental criterion of living protoplasm is its capac-
ity to get excited. Because of this irritable nature it does
something — it reacts like a living thing. The "organ-system,"
or mechanism of reactions, is the nervous system in man
and in all animals with a nervous system. But just as we
must infer that the ovum can "breathe," although it has no
lungs, we must infer that it can react, although it has no
nervous system.
It is vitally important that at every stage of pre- or post-
natal life the organism have all the structure or mechanism
required for living purposes; it only needs to make living
response to living environment. The nervous system comes
to be the visible mechanism by action in which the organism
makes such vital responses to vital situations.
Our nervous system is the most complex mechanism in the
universe; certainly no other system in our body is to be
compared with it in intricacy or in its unique capacity to
learn. Because of this capacity, the evolution of man became
possible and we are what we are. In fact, the goal of evolu-
tion, as we shall see, was always in the direction of a broader
outlook, a greater capacity to anticipate change and weather
9
WHY WE BEHAVE LIKE HUMAN BEINGS
storm. The nervous system is the only key evolved to unlock
the future. We shall pay due respect to it; at this point we
can only glance at its structural development.
Before the embryo is a month old, a depression or trough
appears on the upper surface of the outer germ-layer. It
deepens. The upper edges come together, forming the neural
tube, so called because from it will develop the nervous
system. In the third month the tube expands at one end into
three sacs or vesicles; the first and third of these divide and
there result five vesicles in all. The walls of these hollow
sacs will develop into the brain; the sacs themselves will form
the ventricles (little belly) of the brain.
The remainder of the neural tube will become the spinal
cord. This, in the four-months' embryo, is as long as the
vertebral column; thereafter the column grows faster than
the cord. At birth, the cord proper reaches only to the third
lumbar vertebrae; but from that vertebrae to the end of the
column the cord is represented by the long terminal filament.
This atavistic ending of the spinal cord is found in mammals
generally, and points back to a time in man's ancestry when
the cord extended the entire length of the column.
The cells of the neural tube send out two processes: one
connects with a process from another cell of the central
system; the other grows out toward the surface of the body.
By birth, all parts of the body are connected by these proc-
esses with central — spinal cord and brain — and by the other
processes, all parts of central are connected with one another.
At birth, all the cells of the nervous system are present.
The new-born will develop no new brain cells, but structural
changes will take place in the nerves which are in control
of the motor mechanism; otherwise the infant would remain
as helpless as when born.
Sometimes the bones of the skull grow together prema-
turely; this prevents further growth of the brain. Such a
brain is called microcephalous and vaguely resembles the
brain of monkeys.
10
THE LIFE CYCLE AND THE HUMAN RACE
Monsters are sometimes delivered in which the brain has
never developed beyond the first month of fetal life — ^the
original nerve plate remains spread out on the surface at
the back of the head.
An English shepherd who died at the age of sixty was
normal except for his very small head. He had a human
countenance, but a vacant stare. He could count his fingers,
but not his sheep or the days of the week. He could talk
simple sentences. His brain was one-third normal size and its
fissures were like a fetal brain of seven months, but lower
in type than that of a chimpanzee. The parts associated with
speech were of the size and form found in anthropoid apes.
It was the type of brain our ancestors had millions of years
ago.
Man's brain is from two to three times larger than that
of the gorilla, but, apart from mere size, man and ape brains
are more alike than are their big toes.
Brain weights vary enormously. The average for adult male
Europeans is about 1,375 grams, for females about 1,235.
The brain of Turgueneff, the Russian novelist, weighed 2,012
grams. It is exceeded by that of only two others ; one was an
imbecile. Next in weight come a laborer (1,925 grams) and
a bricklayer (1,900 grams). Gambetta's brain weighed only
1,294 grams. The largest woman's brain recorded is 1,742
grams; she was insane and died of consumption. The third
largest woman's brain recorded weighed 1,580 grams; she
also was insane.
There is no evidence that size of brain (or of head) is
necessarily connected with actual or potential intelligence.
Usually, large individuals have large brains; men are larger
than women. Large brains have no more units than small
brains: the units are large. A small brain is no more neces-
sarily handicapped than a small hand or a small foot.
We do not use the brains we have. Presumably, we no
more get the maximum service out of our brains than we
do out of our motor-mechanism. For every book on how
11
WHY WE BEHAVE LIKE HUMAN BEINGS
to train the brain there are a dozen on how to train the mus-
cles. But not one man in fifty who goes in for muscle-train-
ing expects to put his muscles to work; he sees physical cul-
ture as physical beauty.
5
We no longer tell friends from enemies by smell; but we
often pick them by the shape of their nose. Man's nose
is not so striking as the elephant's, or even the long-nosed
monkey's, but it features his face and is one of his most
human and superfluous elements. As it is a new acquisition
— it began with mammals — it appears late in fetal life and
develops fully only after birth. Its shape and size are he-
reditary and are distinguishing traits of race. But it has
no more to do with brain power than the handkerchief that
wipes it.
As the olfactory nerves alone are connected with the hemi-
spheres of the human brain, it is inferred that the brain it-
self arose in connection with the sense of smell; the original
brain was a smelling organ.
In mammals generally, the smell sense is the most highly
developed of all senses. In monkeys, it has already begun
to diminish. Some mammals have five pairs of ridges sup-
porting the olfactory organs; some hoofed animals have eight;
apes usually have three. Man has from two to five pairs.
The nose in the human embryo is at first a pair of pits or
])ockets in the skin — the condition in fishes. The external
iiose appears much later.
Man's reptilian ancestors had a supplementary smell
organ between roof of mouth and floor of nose. With this
they could sample odors while eating without having to
sniff. We — in common with other mammals — have its ves-
tige in our Jacobsons organ.
The ear also begins as a pocket, in the first gill-cleft. This
sinks into the head until its outer opening is closed by the
12
THE LIFE CYCLE AND THE HUMAN RACE
tympanum or eardrum. A rare anomaly is an individual with
two, or even three, external ear openings ; these represent the
second and third gill-clefts. In some fishes the opening re-
mains; their ear is primarily a balancing organ. Our equilib-
rium sense organ is also located in the inner ear; if our
semilunar canals are destroyed, we cannot balance ourselves.
We turn our head toward sounds or cup our hands be-
hind our ears; our ancestors turned their ears. We have
vestiges of ear muscles, as do apes. Our external ears are
also degenerate, as are those of the orang and gorilla.
Some ears are small and lie tight against the head, as in the
orang; some are large and stand out, as do those of the
chimpanzee.
At the eighth month the rim or helix of the fetal ear
begins to fold in — an additional sign of degeneracy. But
the tip persists and generally may be felt, often may be
seen, near the middle of the infolded helix. It is called
Darwin's point; Darwin pointed out its vestigial character.
The lobe, or soft lower part, of the ear generally appears
at the sixth month of fetal life, is found in no animals
below apes, and in man has no known use other than sup-
port for ornament. It is said to be larger in women than
in men; it may be absent in either sex.
Our eyes are compound and are made up of the same
three parts that are found in fishes' eyes. First, a cluster
of skin-cells dig in to form the lens; skin grows over this,
becomes transparent, and forms the cornea. Next, a growth
from the neural tube reaches out and ends in a cup around
the lens. This cup becomes the retina; the stalk which
joins cup with tube, the optic nerve. Cells from the middle
germ-layer now enter the cup and form the transparent
matter of the eyeball. The middle layer also supplies the
protecting coat of the retina. As the lens is modified skin
structure, it is subject to the horny change of old age. Hence
"cataract" of the eye; the lens has become covered with a
scale.
13
WHY WE BEHAVE LIKE HUMAN BEINGS
The Asiatic's eye is not oblique. The "slit" appearance
is due to the low nasal bridge supporting the upper lid; the
lid thus folds and appears "Mongolian." This "oblique"
eye is not uncommon in white children at birth; when the
bridge develops slowly it may persist for months, even into
adult life.
In the inner angle of our eye is a little fold of skin of
varying size called the plica semilunaris. It is a rudiment
of the third eyelid or nictitating membrane that cleans the
eyeballs of birds and frogs; their upper eyelid is immova-
ble.
The tears which wash our eyes — otherwise as dirty as our
faces — come from lachrylnal glands in the upper outer
corner of each eye. Some have additional tear glands at
the sides of the eyes, as have reptiles.
Our skin is a double structure. The outside, or epidermis,
is ectoderm; the inside, or dermis, is derived from the meso-
derm. The fetal skin at first is translucent and not unlike
that of fishes. During the third month, the epidermis begins
to become horny, as it is in adult life. It is significant that
if we lose a third of our skin — by fire, acid, boiling liquid,
or flaying — we lose our life.
Color of skin is an inherited trait and is due to grains
of brown or yellow-red pigment in the dermis. Entire ab-
sence of pigment in skin, hair, and eyes is a developmental
defect and results in albinos. Albinism is an inherited trait
and is found in many animals. White blackbirds are as
common as white black men. Pigment is probably due to
secretion of an endocrine gland.
To form a better grasping surface, the skin of man's,
monkeys', and many other mammals' hands and feet is
thrown into minute ridges, especially prominent on the finger
tips. These ridges form loops, spirals, and arches. In no
two individuals on earth do they make exactly the same
pattern. Hence their unique importance as marks of iden-
tification.
14
THE LIFE CYCLE AND THE HUMAN RACE
At the fourth month, the embryo begins to show a fine silky
hair coat or lanugo (down). This begins to be replaced,
even before birth, by a second coat of different character.
The lanugo may persist as "down" on the face of girls and
women, or even all over the body, as on the so-called dog-
faced people of the menageries. The lanugo probably rep-
resents our adult ancestral condition. But no satisfactory
theory has yet been advanced to account for the fact that
man is the least hairy of the primates.
Hair does not grow on our bodies in haphazard fashion,
but in lines and sets of three, four, or five, each set being
the hairs that grew beneath one scale of our reptilian ances-
tors. On certain parts, especially on males in the region
of the navel, may be detected a vortex pattern like that at
the end of the spine where the tail once projected.
Cats "feel" in the dark with whiskers or vibrissas. Man's
eyebrows and mouth and ear hairs seem to be the modified
descendants of such feelers. Actual vibrissas — long, coarse,
stiff hairs — often appear in men, especially after middle life,
generally in the eyebrows, less often on the end of the nose.
Man's hairy coat varies individually and in races. Because
of their hairy bodies, the aborigines of Japan are called the
Hairy Ainu. The amount of hair on the face and the parts
of the body covered by hair also vary in different races.
We inherit finger and toe nails, almost without change,
from our animal ancestors. The nails of our big toe, thumb,
and first and second fingers tend to be flat — as they are in
apes; the arched nails of our other fingers suggest the rounded
claws of certain mammals and are like the long curved nails
of monkeys.
Our skin is rich in glands. These begin to develop during
the fifth month. The sweat glands reduce temperature and
eliminate waste. Sebaceous or fat glands lubricate the skin
and hair, and in certain regions (armpits, for example)
secrete an odor. Such odoriferous glands are generally sex-
15
WHY WE BEHAVE LIKE HUMAN BEINGS
ual in character and are highly developed in hoofed animals.
In the male musk deer of Central Asia the gland is as big as
a hen's egg. Its secretion is the base of certain man-made
perfumes. Consequently, the musk deer is almost extinct.
Mammals take their name from their mammae — sweat
glands peculiarly modified to secrete milk. On the one-month
human embryo appear two mammary ridges extending from
armpits to groin. A milk gland develops at the upper end of
each ridge. The ridge then atrophies and disappears. But
one individual in every 500 has supernumerary glands —
three, four, even seven pairs are not unknown. These are
clearly a reversion to an earlier mammalian condition. In
one case a large gland developed in the middle of the back.
At first a depression appears in the center of the gland —
and so remains in the lowest order of mammals. From the
bottom of the depression many little bases rise; these, in both
sexes, come to form the nipple just before or shortly after
birth. The mammae develop no further until puberty, when,
in the female, they are stimulated to further growth by the sex
glands. As their function is food, and as they have been
known to function in otherwise normal males, they are not
primary sexual characters.
6
Now and then a child is born with a common opening for
the intestine and the urogenital tract. This common vent is
called a cloaca (sewer) ; it is the normal condition in fishes,
amphibians, reptiles, birds, and the lowest order of mammals.
In man it represents a reversion to an ancestral type which
did not disappear until marsupials evolved, millions of years
ago, as the second order of mammals.
The cloacal condition is normal in the human embryo dur-
ing the second month; at that time the intestine and urogenital
ducts end in a common chamber. Not until the tenth week is
16
THE LIFE CYCLE AND THE HUMAN RACE
it possible to distinguish a male from a female fetus. Until
this time the external and internal anatomy is identical for
both sexes.
With the eighth week the cloacal condition ceases and the
embryo develops into a male or a female. Whether it is to
become male or female is probably determined when the
ovum is fertilized. The decisive factor is not known, nor is
it likely that we shall discover means by which the ovum will
develop into male or female according to our desire for son
or daughter. As we shall see later, the sex glands themselves
presumably secrete a hormone which, carried by the blood,
causes the marvelous changes whereby the neutral rudimen-
tary organs develop in one or the other direction.
The anatomical structure on which these hormones may act
consists of four parallel tubes at the hind end of the body,
opening into the cloaca. The outer tubes, or Wolffian ducts,
will carry the male glands; the inner pair, or Muellerian
ducts, will become the oviducts, or Fallopian tubes.
If the embryo is to become a male the inner tubes atrophy;
the Wolffian ducts become the vas deferens; the cloaca open-
ing closes to form the scrotum. If female, the cloaca remains
open; the oviducts grow together in the lower part to become
the uterus, the upper becoming the Fallopian tubes; the Wolff-
ian ducts persist as vestiges in the broad ligament. In the
male the sex glands descend ; in the female they remain within
the pelvic cavity. The migration of the glands in the male
is common to most mammals, but only in man, due to his
upright gait, do the inguinal canals through which they pass
remain weak spots which may permit the escape of a loop of
the intestine, causing hernia.
The significant fact is that the human embryo of eight
weeks has the makings of a male or a female. It follows that
neither sex possesses any anatomical parts which are not
found in homologous parts in the other sex. The beginnings
of all the parts are present from the start; later they come to
17
WHY WE BEHAVE LIKE HUMAN BEINGS
differ. By change, by shift in position, and by growth or
atrophy, the original neutral mechanism becomes male or
female.
Most plants and many lower animals are hermaphrodites
(Hermes- Aphrodite) : the organs of both sexes are combined
in one individual. Higher in the scale of animal life true
hermaphrodites disappear. But sometimes in an otherwise
normal human embryo certain parts fail to complete their
normal development. The result is an individual anatom-
ically neither a fully formed male nor a female; such are
called hermaphrodites. But no human being functions both
as male and as female.
While the sex glands or gonads appear at the sixth week,
they show no structural difference as to their future sex; yet
the cells within under the microscope are already definitely
of one or the other sex. If female, the cells are of the ovum
type, large and rounded; if male, the cells are of the sper-
mium type, very small, very long, and ending in a fine process,
or tail.
The function of the renal organs or kidneys is to preserve a
certain constancy in the blood stream and to eliminate certain
noxious elements from the body. To perform this double
function, three types of kidneys have been evolved. The de-
veloping human embryo, as well as embryos of other mam-
mals, rehearses this story, all three types appearing in pre-
natal life.
The first renal organ to appear, the head kidney, becomes
an appendage of the sex glands. The second, or Wolffian
body, becomes part of the seminiferous duct in the male; in
the female it remains as the parovarium, a vestige in the
broad ligament between uterus and pelvic wall — it is often
prone to disease. Finally, true kidneys develop. These are
at first furrowed, as they remain in some mammals; later they
become smooth. Sometimes the furrows persist, reminders of
earlier days.
18
THE LIFE CYCLE AND THE HUMAN RACE
7
The alimentary canal appears first as a closed tube within
the body. It opens later at each end, the upper opening be-
coming part of the mouth cavity. Below this opening four
crevices appear which represent the internal arrangement of
the fish-like gill-clefts. Below these crevices a single sac-like
structure appears; this divides, and by further subdivisions
becomes the right and left lung. From the region of the
crevices outgrowths of the alimentary canal develop into thy-
roid, epithyroid, and thymus glands. From the extreme upper
end of the embryonic canal develops a portion of another im-
portant gland, the pituitary. The stomach at first is merely
an enlargement of the canal. Just below the stomach two
outgrowths of the canal develop into the important glands of
digestion, pancreas and liver.
Without further details of fetal development it will be
worth while to recall certain variations in the systems of
digestion, respiration, and circulation, which are significant
in light of our animal ancestors.
Our dentition is as well adapted for spinach as for beef-
steak, specialized for neither. Our front, or incisor, teeth
are only fair cutters; our bicuspids, or premolars, are not
strong enough to crunch bones; our grinders, or molars, are
not very good millstones. Our snarling muscle discloses no ^
such canines as the flesh-eaters stab and tear their prey with.
Our teeth are on the go. A perfect "civilized" set is rare.
In hundreds of skulls I collected in New Guinea there was not
one imperfect set — all strong, sound, beautifully aligned.
Man, apes, and Old World monkeys have thirty-two teeth,
eight on each side of each jaw: two incisors, one canine, two
bicuspids, three molars. Man's mammalian ancestor had
forty-four teeth: three incisors, one canine, three bicuspids,
four molars.
Variation rules. Often there is only one incisor, an in-
herited condition; there may be three incisors. The canine
19
WHY WE BEHAVE LIKE HUMAN BEINGS
is rarely absent, but it may be a tiny stump; more often it
is over-developed, disfiguring the face. A third bicuspid is
not rare. A fourth molar is more rare, but frequent enough
to be suggestive. The third molar, or wisdom tooth, is a bad
lot among whites — jaws too short; it comes in at any angle,
varies in its cusps, often is a mere stump, often never erupts
at all.
Most fishes have teeth in the roof of the mouth as well as
in the jaws proper. They do not occur in "sets," but are end-
lessly shed and reproduced. In the fish embryo the dental
germs appear before the jawbones; in the human embryo also.
In the infant's mouth is a ridge with from five to seven pairs
of cross ridges; they are even more pronounced in the fetus.
They disappear with age. Apes have ten pairs of these
ridges. In pigs, they are strong enough to crush food. Their
presence in man, with an occasional more or less complete
third set of teeth, points to fish and reptile days: teeth in the
roof of the mouth, endlessly replaced.
Tonsils appear in fetal life as pockets. They shift position
and develop into prominent bodies. With adult life they be-
gin to disappear, leaving pockets prone to disease. They
are not understood and are never alike.
The cricket's chirp was the first music on earth, but it was
instrumental. The first voice was the amphibian's. Frog,
bird, cat, dog, and man would be silent without a larynx;
without the human larynx there could have been no human
speech or Tower of Babel. Ours is a wonderful larynx; let
us get such joy as we can from it. Our developing respira-
tory system suggests fish; in our youth it is a hotbed of infec-
tion. Our vocal cords are human only in their high develop-
ment. But we all have the blind pocket between true and
false cords which served as a resonator and so strengthened
the roar by which our ancestors frightened their foes and
called their mates. In man it varies, but is never so deep as
in the gorilla.
The vermiform appendix is the worm its name implies. It
20
THE LIFE CYCLE AND THE HUMAN RACE
is a feeble, narrow, tapering blind alley, opening by a small
moiitli into the large intestine. At birth, in size and form it
is like an ape's. At puberty it begins to shorten; it is about
closed in every fourth adult; in every thirtieth adult it is
closed throughout. It shrivels up with old age. It may be ten
times longer in one brother than in another. It is a true
vestige. It is predisposed to disease; appendicitis is a fash-
ionable operation. Only apes in captivity develop append-
icitis. For an appendix that functions we must go to the
lowest monkeys.
The liver usually has two lobes — it may have none, it may
have twelve; it may have two gall-bladders — it may have
none.
The abdominal viscera in the human embryo are not human
in their arrangement. Only later does the mesentery, or sheet
of membrane connecting the bowel, become attached to the
back wall of the abdomen and so hold it in place and in per-
pendicular position. Sometimes the mesentery is found ar-
ranged as in monkeys. The loosely attached bowel easily
twists and becomes obstructed.
There are more than mere structural variations in our food
canal; there are signs of degeneracy — in teeth, in jaws and
throat, and in the large intestine. Changed diet does it. To
digest raw food our ancestors had to chew it. They had strong
jaws, heavy muscles, sound teeth properly aligned, big throats,
and a colon that could digest husks of grain and skins of
fruits and vegetables.
The lobes of the lungs vary in number and position. Due
to man's upright gait, the heart has come to rest on the dia-
phragm. In monkeys the azygos lobe of the lung lies be-
tween. In man there is always a remnant, of varying size, of
this lobe.
The chief business of the fish heart is to pump blood to the
gills; of ours, to the body. The human embryo at the bran-
chial-cleft stage has a tubular heart of four chambers. When
lungs begin to develop the first chamber becomes part of the
21
WHY WE BEHAVE LIKE HUMAN BEINGS
auricle, the fourth chamber part of the ventricle. These then
divide into right and left; the right passes venous blood to the
placenta, the left receives this blood and sends it to the body.
The fourth chamber may fail to develop normally; the blood
passes imperfectly into the pulmonary artery and so is not
properly oxidized. Sometimes a heart is found with the ves-
tige of a valve which functions in animals no higher than
frogs and salamanders. Variations in the blood vessels are
endless. Even the great artery leading from the heart is sub-
ject to astonishing variations — all harking back to great
changes in the circulatory system since man evolved from a
water-breathing animal.
When we recall the branchial-clefts in the neckbend of the
human fetus — and their fate; also that for ages man's an-
cestors derived their oxygen from water through gills and not
from air through lungs; also that man only recently left the
trees — ^we must expect to find great variation in human mouths
and throats, in the food and air canals below, and in the
marvelously intricate system which delivers blood to every
cell in the complex body.
8
Suppose it's twins! One in every hundred births is. Ire-
land averages higher — one pair for every seventy-two births.
Twins run in families. A mother who has twins is likely
to bear more twins. She is called a "repeater." She prob-
ably inherits twin capacity — and transmits it. Her anatomy
is such that twins are possible. That she bears twins only one-
fifth of the time is probably due to her own internal weak-
ness. Twins occur also in other mammals that ordinarily
bear but one individual at a time. Triplets occur once in
every 7,000 births; quadruplets, only once in every 370,000
births.
There are two kinds of twins: twins; identical twins. The
first type develops independently from two ova that happen
22
THE LIFE CYCLE AND THE HUMAN RACE
to mature at the same time. Each ovum develops its own
chorion and placenta — though the two placentas may partially
fuse. They are not true or "identical" twins, merely acci-
dents as to time of birth. Both may be boys or girls, or
they may be brother and sister. They vary as brothers and
sisters of a family normally vary.
Identical twins are always of the same sex: either both
boys or both girls. They develop from a single ovum, in the
same chorion, and receive food and oxygen through the same
placenta, to which each is attached by its own umbilicus.
There need be no doubt as to whether twins are just twins
or identical: if identical, they are always of the same sex
and there is only one placenta ; if there are two placentas, or
if they are of different sex, they cannot be true twins.
Sometimes identical twins are so alike that only a string
around the thumb, or some such device, will enable the mother
to distinguish one from the other.
It was formerly held that identical twins, triplets, quad-
ruplets, etc., resulted from multiple fertilization of one ovum.
But twins and monsters can be produced artifically in biologic
laboratories. Fish monsters can be grown from eggs deprived
of enough oxygen. Monsters of all sorts have been grown by
separating the young embryo into two or more parts. Perfect
twins have been grown from the two cells of the dividing
ovum shaken apart.
Human twins, triplets, etc., presumably arise from early
separation of the ceils into which the original ovum divided.
If the division is not complete, the result is twin, triplet, or
even quadruplet monsters. These may take any conceivable
form, from twins bound together only at one spot, to a twin
inside the body of the other. An autopsy recently revealed
a tiny parasitic twin in an abdominal tumor, carried within
its twin brother's body for half a century. He had never
known of its existence.
Double monsters may have one head, two bodies; two
heads, one body; one head, two necks, one chest, two bodies
23
WHY WE BEHAVE LIKE HUMAN BEINGS
below the diaphragm. One twin may be fully developed;
attached to its body is an arm or a leg of the other. One twin
may develop no heart, receiving its blood through its umbili-
cus; it perishes at birth.
In "Siamese" twins, the embryo divides into two at both
ends but not in the middle; if they share vital organs, they
cannot be separated by the knife. The Two-headed Nightin-
gale, Millie and Christina, had two heads, one body, four
legs; she (or they) could sing by each head and each head
could control two or four legs. The famous Scottish Brothers
— clever musicians and linguists — were one individual below
the waist, above quite distinct except at the back.
Single monsters may have no arms or legs ; no abdominal
wall ; a brain outside the skull or other malformation of brain,
skull, or face; a Janus face; a Cyclopean eye. There is no
end to the range of malformation.
Other abnormalities are only to be understood in the light
of man's ancestry. Part or parts stop growth before normal
human condition is reached. They point the road man trav-
eled. Some are not easy to classify: vestiges of ancient days,
part of our normal heritage; faulty cell division, unfavorable
environment, faulty implantation, or defective germ-plasm?
In one unique case the ovum had become implanted clear out-
side the abdominal cavity, just under the skin over the ab-
domen. It had begun to develop and was diagnosed as a
tumor.
The lower jaw may be deformed; no sharp line between
face and neck, ears almost meeting in front. Reversion to
a fish condition? No doubt as to what happened — the first
gill-arch of the embryo failed to develop. It hardly de-
velops at all in lowest fishes.
There may be an extra finger or toe, always outside
thumb or little finger. Is this an ancestral echo, or did a
finger-bud divide? The tenth-of-an-inch-long four-weeks-old
fetus' limbs begin as tiny buds and soon look like paddles.
Before the buds appear, the fetus is limbless. Sometimes
24
THE LIFE CYCLE AND THE HUMAN RACE
the paddles never develop into arms or legs; they remain
mere flaps. Or, the fingers and toes may remain hidden
in the flaps. Or, some or all of the fingers or toes may be
webbed — as they are in the embryo.
Rabbits are not "hare-lipped"; their upper lip is cleft in
the middle. Our lip begins as three pieces; if they fail to
join, the cleft is between one or both nostrils and the mouth
— never in the middle of the lip. A double "hare-lipped"
man is shark-lipped.
We can eat and breathe at the same time because our
mouth is shut off" from our nose by the palate or, roof of
our mouth. Our palate begins as two bones; they join in
the ninth week of fetal life. Sometimes they do not; result:
cleft palate, as have frogs, snakes, and birds.
Cysts or hollow tumors may be found in any part of the
body. When lined with skin, they are called dermoid. They
are thought to arise from germ-cells which strayed away
from the sex-glands.
Generally, abnormal development is due to disease in
the uterus or to such faulty attachment of embryo that its
nourishment is impaired. But ova may develop normally in
abnormal positions, even outside the uterus. Mothers can-
not influence their intrauterine growth by "scares," etc.
Possibly her blood altered by fever might upset normal de-
velopment. It is known that tetanus, diphtheria, and typhoid
toxins and antitoxins can pass from the host into fetal cir-
culation. It also seems that the germs of typhoid, and
possibly tuberculosis, may similarly pass from host to fetus.
But it must be understood that there is no interchange of
blood between the two, nor any commingling of body fluids
or nerve tissue. The fetus is a true parasite.
9
In upright gait, balanced skull, and arms free at the sides
of the body, we diff"er most from the only animals that ape
25
WHY WE BEHAVE LIKE HUMAN BEINGS
us. This upright gait is maintained by action of muscle
on bone. We hang on a bony skeleton, largely levers. We
move by setting those levers in motion. To put us across
a hundred yards in ten seconds, the skeleton must be mature.
If our bones were cartilage we would be wonderful con-
tortionists, but our upright gait would collapse.
Our ancestors went on all-fours. In acquiring the up-
right gait, the axis of the body changed from horizontal to
perpendicular. This necessitated changes in every bone and
muscle in the body and a complete overhauling of every-
thing inside — lungs, circulation, abdominal viscera^ — every-
thing.
Our pelvic girdle is a broad, shallow basin; it supports
viscera. The keystone of the girdle is the sacrum. It sup-
ports the backbone and locks the arch behind. The dog's
sacrum is long and narrow; ours, broader than it is long.
The sacrum at birth varies from four to seven vertebrae.
These unite into one bone; but the first, and sometimes the
second, never unites with the others.
Above the sacrum is the vertebral column proper: seven
neck or cervical, twelve thoracic, and five lumbar vertebrae
— -twenty-four in all. But there may be six or eight cervical;
eleven or thirteen thoracic; four to six lumbar. At birth,
most of us have twelve pairs of ribs ; some, only eleven ; some,
thirteen.
Seven pairs of ribs join our sternum, or breastbone; there
may be only six, there may be eight. The first pair are
sometimes mere rudiments. Our floating ribs are not so
important as when we walked on all fours; they vary in
number and size. The sternum is less important than for-
merly; it varies enormously. Two little bones sometimes
found on its upper border are vestiges of tlie episternal
bones of the lowest mammals.
No man-made column is so delicately adjusted, so slender,
or so well balanced as our spine. Its sigmoid, or "S" curve,
gives elasticity to our body, grace to our carriage, fine lines
26
THE LIFE CYCLE AND THE HUMAN RACE
to our back, and saves our brain from jar and shock. The
really human curves develop after birth, especially the lum-
bar curve in the "small" of our back. The infant cannot
stand straight up because it has not yet acquired a stand-
up-straight backbone.
Our backbone ends in small rounded bones about the
size of peas. They are the coccyx, skeleton of our tail.
They may grow fast to the sacrum, and by restricting the
size of the pelvic opening give trouble in childbirth. The
orang has only three tail bones; we generally have five.
Like the apes, we also have vestiges of muscles which once
moved the tail, blood vessels which nourished it, nerves
which connected it with the brain.
There is no tailed race in Africa — as the ancients be-
lieved. Man withdrew his tail beneath his skin before he
was really man, but nature now and then forgets to with-
draw the fetal tail. One adult tail measured ten inches.
Such tails are usually "soft" — no tail bones outside the
body. But a two-inch-long tail with bones, nerves, blood
vessels, muscles, and hair, is known. Tail or no tail, the
hair keeps on growing in a whorl as though the tail were*
present.
The upper-arm bone assumes its human form only after
birth, when it also begins to twist, as does the femur, to con-
form to its new position at the side of the body. Above its
lower articulating surface is a thin and shallow plate, often
perforated — as in certain monkeys. Sometimes there is a
hole or foramen at the side; it protects a nerve — as it did in
our reptilian ancestors ten million years ago.
Human history may not start with man's foot, but our
foot is as human as our hands. Its bones show coming and
going changes. The big toe is the strongest and is more
powerful in man than in any ape: it is coming. But most
of it comes after birth; baby's big toe is a poor affair. The
little toe is going. In one individual out of every three it
has lost a joint. But not on account of tight shoes — they
27
WHY WE BEHAVE LIKE HUMAN BEINGS
can make corns, but cannot change heredity; the third bone
of the little toe is as often absent in feet which were never
shod.
Our skull is no more human than are the bones of our
foot or of our pelvis. It is shorter in front, longer at the
back, better balanced on the spine: adaptations to an up-
right gait and a larger brain.
Man has a flat face and a sizable chin when he has short
jaws. But jaws vary, and long or prognathic jaws change
the countenance. The roof of our mouth was once longer
than broad — U-shaped, as in some men and all apes. With
civilized food, the jaws are shortening; the hard palate
tends to become elliptical in shape.
In fetal life we have a pair of intermaxillaries between
the upper jaw bones. At birth the suture, as skull joints
are called, between them can barely be seen; by maturity, not
at all. The suture often persists, obviously atavistic. The
chin, or mental point of the lower jaw, has nothing to do
with "mentality." It is a human trait, but not of all men
equally. Some have "strong" chins, some next to no chin
at all.
We have two nasal bones. But in some men and all
monkeys they become one; no real bridge then to the nose.
Sometimes the bones are small and flat: no bridge at all.
The brain can grow only as long as the three big sutures of
the skull remain open. They begin to close at the age of
forty: the one at the back first; the fore part of the brain
can keep on growing. In animals the sutures close earlier
than in man, the front ones first. They may close early in
man; they may persist till old age.
WThen one or another skull suture closes prematurely,
curiously shaped heads result. The "boat-shaped" head is
due to premature closing of the parietal suture. When all
the sutures close prematurely, the skull becomes solid as
though a single bone. The brain can grow no more. Idiocy
results — the "Aztec" people of the circus.
28
THE LIFE CYCLE AND THE HUMAN RACE
The frontal bone begins as two; shortly after birth they
have become one, the suture disappears. But the suture
may persist throughout life.
Most of us have about 310 muscles on each side of our
body. They are subject to such variation that Testut, a
noted French anatomist, required 900 pages to describe
them. Some of us may have 3 muscles an ape would be
ashamed to own, hangovers from such a remote past.
We marvel at the agility of monkeys and are astonished
at the human quality of their actions. Do we not often
expect them to smile? The smile never comes: they have
no muscle to smile with. Even the chimpanzee cannot ex-
press with its face the emotions we think it should; its
facial muscles are less perfectly developed, less sharply
defined, than ours. In monkeys, they are even less differ-
entiated.
One- fourth of all our muscles are in our neck and face!
The human face can light up or cloud over because its
muscles are attuned for complex action — keyed to the human
pitch.
Facial muscles in mammals below man are more simple.
We look for intelligence in the eyes of a horse, not in the
expression of its face. When it needs to flick a fly from its
face or shoulder, it moves a muscle buried in the skin.
Such a muscle covers many animals like a blanket.
We all have bits of this skin muscle — some of us more,
some less, even on the chest and back. Usually we cannot
twitch it; we send a hand after the fly. We have traces of
it in our scalp; a few have enough to move the whole scalp.
Most of us can wrinkle our forehead — and do, when per-
plexed. Apes use this muscle both in pleasure and to frighten
enemies. We all have vestiges of the muscles dogs use to
pull, push, and lift their ears; some can even wriggle them.
So, while the skin muscle of our face and shoulders tends
to disappear, the deeper facial muscles show progressive
variation. They are among our most recent acquisitions. We
29
WHY WE BEHAVE LIKE HUMAN BEINGS
retain the muscle by which the dog shows its canine tooth : w^e
can all snarl. But the muscle by which we smile is not so
regularly present; the man of gloom may have no risorius.
Variations in muscles about the nose and mouth, necessary
for speech, are usually forward-looking; they give the
"speaking likeness" to man. Often they reveal what the
mind is trying to hide. Only as we grow in experience can
we make our face a mask to belie our emotions. This is
because the face is primarily under the control of the auto-
nomic nerves; they act of their own sweet will and are by
nature honest. But by and by our brain learns to get con-
trol of them; we force our face to wear a smile when our
heart would bid our eyes to weep.
The long flat rectus muscles which extend upward from
our pubes once helped to support our abdomen. In our
upright gait they are of no great use. Usually they end in
the fifth, sixth, and seventh ribs; they may end in the fifth;
they may extend up to the second, as they do in the lowest
monkeys.
The small pyramidalis resting on the rectus abdominis
muscle may be absent on one or on both sides ; it may extend
a third of the way up to the navel, or all the way. The
kangaroo needs it to support the pouch in which she carries
her young. Man has carried his young in his arms for ages,
but the pyramidalis hangs on like a bad habit. The little
sternalis muscle of the breast knows it has outworn its use-
fulness; it is found in one of every twenty- five individuals.
We flex our fingers by delicate muscles beautifully special-
ized. The long clumsy flexor of our palm was good enough
for our ancestors; it is not good enough for us. It is absent
in one man out of every ten.
Our arms are free; they have not forgotten that they were
once legs. Of 36 bodies examined, 292 variations were
found in the arm muscles, 119 in the leg. Our immediate
ancestors were four-handed, we are two-footed. But when
baby gets on the floor, it pulls with its fore and pushes with
30
THE LIFE CYCLE AND THE HUMAN RACE
its hind limbs: just as we once crawled up out of water on
to dry land.
Palmists rarely read the pad at the outer edge of our
palm — or know that we have one like it on the sole of our
foot; both protect deep-lying muscles from injury in walk-
ing. The palm pad has its own palmar muscle in one man
out of every ten. It helped to work the pads which pro-
tected the muscles and tendons beneath. To-day, it is as
atavistic as the pad itself; we gave up walking on our hands
about 2,000,000 years ago. As for "lines" of fate and
marriage, and the "girdle of Venus," they can all be "read"
in the hands and feet of monkeys, and to a certain extent in
a baby's foot — or in the fetal hands and feet. Palmistry is
as dead as phrenology. Anyone who can read "character"
or "mental capacity" from head bumps or palm lines is a J
wizard and should be paid accordingly.
What does it all mean, this astounding range of varia-
tion, on which I have barely touched? There they are, by the
thousands, by unnumbered thousands. Shall we say that
they lie, that our levator coccygis never lifted a tail, that our
curvator coccygis never curved one, and that our attollens
auriculam never lifted an ear? Or shall we say that we
are walking museums of comparative anatomy and try to
find out whence we came and whither we are going? This is
certain: there is no fixed, standardized, perfect, or biolog-
ically ideal human body; there are no two human bodies quite
alike. Each one of us reeks with evidence that our ancestors
were not the two-handed, two-footed creatures we are now;
that they had no talking muscles; that they could not back
up their talk with a speaking countenance; and that they
could not balance their heads on their spines.
Some variations are atavistic or vestigial. Like the buttons
on our coat cuff's, they no longer function; like parlor
boarders, they often make trouble. They are hangovers
from a remote past. They are prone to disease; we should
be better off" without them. Some are retrogressive, weak
31
WHY WE BEHAVE LIKE HUMAN BEINGS
sisters of our body, functioning in a half-hearted way; we
could do without them — many of us do. Some are progres-
sive, a little bit more than human; they point to further
change in man's physical structure.
Taken together, they bridge every gap and make a com-
plete story. They prove that, while our eyes look forward,
our body has not forgotten its humble origin — and carries
some dead wood we were well rid of, such as appendix, tail,
snarling muscle. Our proneness to hernia and prolapse of
the uterus is only one of the many proofs that our body is
not yet perfectly adapted to an upright gait.
10
On the day we are born we have used up only 2 per cent
of our allotted growth power. We can grow 98 per cent more
if we are spared.
We double our weight the first six months; a calf does it
in fifty days; a dog, in eight. We increase our weight 200
per cent in the first year, less than 30 in the second, only 5
in the fifth. Increase in weight then picks up again and
continues until the tenth year, to drop back from the eleventh
to the thirteenth. From the fourteenth to the seventeenth,
puberty years, it increases again, to 12 per cent. That is
our last spurt. It drops to 4 per cent during the eighteenth
year; to 1 per cent during the twenty-second.
Stature also increases by spurts. By the time the infant
can walk, it has grown from twenty to thirty-four inches;
thereafter, until puberty, it grows between two and three
inches a year. The thirteenth is the rapid growing year
for girls, the sixteenth for boys. Between fourteen and
sixteen the boy increases his stature eight inches. Girls
usually attain their full stature by twenty, sometimes by
eighteen; boys by twenty-five. But both may continue growth
three or four years longer, boys even up to thirty- five.
The newborn's brain is already one-fifth its destined weight,
32
THE LIFE CYCLE AND THE HUMAN RACE
about ten ounces; by the second year two-fifths, or as large
as an adult anthropoid ape's. Full brain weight comes
before twenty- five; after that it loses weight, rapidly in old
age.
The body changes proportions during growth. At twenty-
five years the middle point of stature cuts across the pelvis
— legs make up half the total length; at birth, only three-
eighths; of a two-months' fetus, only one-eighth. Adult man
cannot easily walk on all-fours; at birth he is better pro-
portioned for an all-fours gait than a gorilla.
The two elements in growth are weight and height. Weight
often continues beyond maturity, long after the body has
taken on its last cubit. The giant can grow no taller; the
fat lady knows no limit.
In prenatal life weight increases by growth, division, and
growth of cells. A bacterium increases its weight by 1,000
per cent in a few hours; the human embryo at first grows
at least as fast. Weight after birth increases in the size
rather than in the number of the cells of the body.
Stature is determined almost entirely by the skeleton. Only
skin and a thin layer of fat cover skull and the bones of the
feet; thin cartilage covers the ends of the leg bones; between
the vertebrae are thin pads of cartilage. Stature growth,
then, is largely a matter of growth of skull, bodies of verte-
brae, and especially of the leg bones.
Bones grow from centers of ossification. Centers for the
principal bones of the body appear by the end of the second
month of fetal life; centers for the ends, or epiphyses, appear
later — many not until puberty, when the skeleton begins to
assume its permanent form.
The number of ossification centers varies in different bones.
The long bones of the arms and legs have at least three: one
in the shaft itself and one at each epiphysis. The humerus
at fifteen years is still in three parts: shaft, two heads; but
the heads are more closely connected with shaft than at birth.
33
WHY WE BEHAVE LIKE HUMAN BEINGS
By maturity, the heads are so united with the shaft that it is
not possible to see where they grew on.
In general, facial and skull-dome bones are formed from
membrane — "skin" bones ; the other bones begin in cartilage.
Bone-forming cells multiply by division, absorb lime salts
from the blood, ossify, and so continue until the cartilage is
replaced by bone. Increase in length ends when the cartilage
disappears. In the mature skeleton there can be no further
growth in stature or in length of arms. If final conversion
of cartilage to bone is delayed, gigantic stature results ; if the
process is reversed, dwarfs. Only the articulating or joint
surfaces of mature bones are covered by cartilage.
Bones increase in girth by additions of bone cells from the
surrounding membrane. Long bones are hollow. To pre-
serve their relative proportion of bone wall to cavity, bone
cells on the inside are destroyed as fast as cells are added to
the outside. Thus the cavity grows with the bone, the form
and strength of the bones are preserved. This process keeps
up until late in life. With old age the bones become thin
and delicate.
11
Complicated changes take place in acquiring the upright
gait. A chick can run from its shell; a baby cannot even
straighten its legs. They bend in at the knees and are drawn
up at the hips, and are only 60 per cent of head-trunk length.
By maturity they will be over 100 per cent. As the walking
days approach, the legs grow fast. Knee and hip joints
change; the legs can now be straightened out. The soles of
the feet no longer turn in. The baby at birth can clap its feet
almost as easily as its hands.
The spine also changes. It is not solid, but consists of
twenty-four vertebrae with pads of cartilage between. At
birth a large percentage of the column is cartilage. Power-
ful muscles develop to hold the spine erect; others, acting on
34
THE LIFE CYCLE AND THE HUMAN RACE
the ribs as levers, to balance the trunk and spine. The last
five, or lumbar, vertebrae at birth make up 27 per cent of
the total spine length, as in adult chimpanzees ; in adults they
make up 32 per cent. The first two lumbar vertebrae take
on their wedge shape which produces the curve in the small
of our back only after birth. When the baby first tries to
stand, it bends backward at the loins.
Standing is a complex act involving nearly all our big
muscles. When we stand "at attention," powerful ligaments
in the hip joint hold the body. This relieves the muscles from
strain, but locks the knee joint. We stand easier if the knees
are slightly bent and the knee-caps loose.
The feet muscles must bind the many small bones together
to give support and form the instep or arch. A man can
stand up asleep, but not if muscles of feet or of legs are
"asleep."
In walking, each leg rests half the time. We tire standing
because neither leg gets rested. The shoulder muscles which
hold the head erect also ache from the strain in standing. As
we nap in a chair the head nods.
Flat feet are not due to a giving way of ligaments; liga-
ments limit joint movement. Feet become "flat" when the
muscles of the arch fail to support it; the arch breaks down.
The result is a mid-tarsal joint. This is most likely to happen
in long, narrow feet.
Short feet and high insteps go with large calves. To raise
our body on our toes, we lift our heel. The toes are the
fulcrum, the power is the calf muscles; the weight falls on
the foot at the ankle joint but nearest the power at the
heel. Hence the greater need for large calf muscles. But
small calves go with long heel bones. As the foot is a
lever of the second order, the long heel brings the weight
nearer the fulcrum — that is, the toes. Hence "flat-foots" do
not step off" their toes; the fallen arch destroys the lever of
the foot.
We nod our head between skull and first vertebra, or atlas ;
35
WHY WE BEHAVE LIKE HUMAN BEINGS
rotate, between atlas and second vertebra, or axis. Both
movements are limited by ligaments; otherwise the spinal
cord would be crushed.
The main business of the face is to hold the teeth-bearing
jaws; eyes and nose moved in by accident. The infant's
face and neck seem small because the brain is so large.
Their real growth begins with the eruption of the teeth.
The skull is a fulcrum for the jaw muscles in chewing.
Muscles to hold the fulcrum steady develop with the teeth.
The neck grows larger. With the teeth all in place the
neck reaches normal size, the rounded "baby-face" disap-
pears; strong jaws, powerful muscles, and prominences and
ridges on bones of face and head support the muscles of
mastication. The tiny mastoid processes below the infant's
ears become adult structures as big as thumbs, required for
muscle support.
The first, or milk, teeth should be in place by the end of
the second year. Meanwhile the transverse ridges in the
roof of the infant's mouth disappear. The permanent denti-
tion begins with the first molars in the seventh year; incisors
in the eighth and ninth; premolars in the tenth and eleventh;
canine and second molars in the thirteenth to fourteenth ; third
molars, or wisdom teeth, in the seventeenth to fortieth year.
Startling changes of far-reaching consequence mark the
years of adolescence for both sexes. As these changes are
both physical and mental, and as they proceed under impulses
from the gonads acting as glands of internal secretion, they
will be described in the chapter devoted to the endocrine
organs.
After maturity the body's chief task is to maintain its
equilibrium: produce enough energy and heat to keep up
repairs and carry on. But, from ovum to death, the body
never ceases to change. Senility may be postponed; the
body begins to age the day the ovum begins to grow. Before
the newborn can mature, it must grow more human. Before
36
THE LIFE CYCLE AND THE HUMAN RACE
it is twenty years old, it will increase its weight from fifteen
to thirty times. Thereafter it grows old at a less rapid rate.
Old-age or senile changes precede natural death. These
appear toward the end of a span of life which varies in differ-
ent species. This span of life for some invertebrates is less
than 100 hours; for some insects, 17 years; for some fishes
and reptiles, over 200 years; for some birds and mammals,
120 years.
Absolutely authenticated cases of human beings alive be-
yond 100 years are almost unknown. It is far from certain
that Thomas Parr lived 152 years. A critical examination
of nearly one million cases of alleged unusual longevity
showed none over 100, and only thirty that lived that long;
twenty-one were women.
Longevity is not, as Weismann claimed, related to size of
body. Some mammals live less than two years, some locusts
seventeen. A dog is old at 20. I have seen a parrot 117
years old; it matured in its first year. A tortoise can live
350 years. No elephant known has exceeded 130 years.
Nor does death "naturally" follow the reproductive stage;
innumerable animals long survive their sex life. But every
animal must reach sex maturity or its kind dies with it.
Old age is decrepitude; the body is worn out. The mechan-
ism the infant acquired to walk with breaks down. The spine
is not so supple, the cartilage disks between vertebrae shrink.
This decreases stature — as much as three inches after fifty.
The spine both collapses and "stoops with age." The knees
are bent, the hip joints stiff. The muscles shrink. The body
loses its natural fat. Folds of skin appear on neck and
face. The toothless jaws atrophy and the mouth loses its
shape. Cheeks and temples cave in, the bony scaffold be-
neath stands out.
The brain loses weight — in the last forty years of life as
much as three ounces. The heart is enlarged from over-
action to keep the blood coursing through thick, hard arteries.
The pulse mounts again. It was 134 at birth, 110 at the
37
WHY WE BEHAVE LIKE HUMAN BEINGS
end of the first year, 72 at twenty-one. After eighty, it is 80.
The lungs lose their elasticity, the walls become thicker.
Many women after fifty show a thicker neck, hair on the
face, deeper-toned voice, more prominent cheek-bones, ridges
over the eyes. Their "feminine" traits are less feminine. It is
as though the inactivity of the gonads permitted a return to a
neutral condition, halfway between male and female.
Old age, senility, decrepitude; the body is worn out, it can
no longer function. Death.
12
There are no two human beings quite alike; every human
being in the world is unique. And yet there are about seven-
teen hundred million beings in the world to-day so much
alike in body and behavior that without hesitation we call
them human; they all belong to the human race. Nor is
there any doubt about the striking physical differences be-
tween a white-skinned, blue-eyed, fair-haired Scandinavian
and a black-skinned, black-eyed, frizzly-haired Senegambian.
The Scandinavian and the Senegambian are so different that
they could not possibly be mistaken one for the other. Do
they belong to the same race?
Recently I came across this heading: "Races Now Well
Defined"; and here is a sample definition: ''Asiatic or Mon-
golian race — yellowish color, dark hair and brown eyes,
character cruel and avaricious, fond of show, likes to dress
in flowing garments, and is ruled by prevailing opinions!"
This is sheer nonsense. Here is a better one: ''Caucasian or
European race — white skin, red cheeks, brown hair, round
skull, oval face, smooth forehead, narrow nose, small mouth,
perpendicular front teeth, face symmetrical; and agreeable."
Agreeable race, therefore!
Most of this confusion dates from Blumenbach's scheme
of five races, one for each continent. But as a matter of fact
no anthropologist knows where "Caucasian" leaves off, where
38
THE LIFE CYCLE AND THE HUMAN RACE
"Mongolian" begins. Boas, our foremost anthropologist, once
addressed a Japanese in an Indian tongue of the northwest
coast of America — ^he thought the Jap a native American! I
could pick a dozen old women out of Peking, dress their
hair and put them in beaded buckskin, and defy Congress to
tell whether they are Arapaho, Manchu, Chinese, or "Mon-
gol."
is a biologic term and has to do with physical
characters based on blood relationship. The extent to which
environment may alter the physical features we are born with
is still an unsolved problem. There is no Aryan or Semitic
race, because "Aryan" and "Semitic" are linguistic terms and
refer to peoples who learn to speak an Aryan or Semitic
dialect. In other words, race is the naked body we are born
with; language and culture, the duds we learn to wear — often,
in civilization, with much discomfort. There are varieties
or types of men on the one hand ; on the other, groups, tribes,
nations, having a common language or a common culture or
both. To classify people by language or culture is one thing;
to classify man by physical traits is quite another.
There are Negroes in America of African ancestry; they
speak English, are civilized, Christian, American. Trans-
plant them to Africa: they cannot get rid of their physical
features; they may forget or retain their English or acquire
a new tongue — or a half-dozen ; they may retain their "civili-
zation"; they may become Mohammedans and adopt Arabic
culture; or they may become cannibals and found a slave-
trading kingdom.
A man's great-grandmother may have been Indian, his
other ancestors mixed Irish, Swedish, Spanish, and Turkish:
that man is white, Caucasian, Aryan, and may be "Nordic."
For "Indian" substitute "Negro"; if any of the Negro shows
through, he is a Negro! This gives us the emotional element;
prejudice is at work. Clothes and the barber go far to
make the man, but prejudice trains the eye to detect signs that
39
WHY WE BEHAVE LIKE HUMAN BEINGS
would otherwise never be noticed. A Negro of Atlanta is
often a white north of Dixie.
The emotional factor takes it for granted that moral and
intellectual values inhere in skin color, language, culture,
and nationality. H. G. Wells's heart beats faster in nearly
every chapter of his Outline of History, because he cannot
forget that he is Nordic, Aryan, English, British, white, civi-
lized. Are these traits innately or necessarily related?
Assuming, as every biologist does, that man's ancestor was
a monkey before he was an ape, is the blond Caucasian a
"higher" type than the dark Ethiopian? Is one the end, the
other the beginning, of human evolution? In other words,
are there higher and lower races? Common sense says "yes."
Common sense also said: There are ghosts. Witches turn
milk blue. Any idiot can see that the earth is flat!
If I measure by my foot and weigh by my body, I can
grade the whole human race from myself down to the lowest,
blackest Pygmy. Man is usually measured and weighed that
way, and with the same result: "high"; "low." The "highest"
are the whitest; the "lowest," blackest: when the grader is
white. It is good psychology — self-love is the first law of
life — but not good biology. Imagine dogs graded from
"high" to "low" by a Pekinese pug, a Mexican hairless, a
Scotch collie, an Australian dingo; or pigeons graded by a
pouter, a carrier, a fantail, a tumbler, a rockdove!
Color probably has no biologic significance; it may have
physiologic value. Nowhere in the plant or animal world
is it a mark of high or low, or of progressive or backward.
Man's skin color is partly determined by exposure, mostly
by an inherited mechanism which regulates pigment. How
or why this mechanism works, how it arose and why it varies
as it does in man, we do not know.
Pigment is probably a waste product of cell metabolism; it
contains iron; it is possibly a response to living tissue's need
for protection from harmful light rays. This does not help
much. Why are Eskimos brunettes, Icelanders blonds? Wliy
40
THE LIFE CYCLE AND THE HUMAN RACE
are the Amazon forest natives "red," those of the Niger
forests black?
All humans (except albinos) have skin pigment; it is the
amount that counts. A white skin may turn dark bronze in
Addison's disease. White skins develop black moles and
tumors, and even general melanosis — dark pigment is carried
by the blood and deposited throughout the body.
Much is known of man's anatomy at the dawn of the
human race; the color of his skin and other details are not
known. Fossil bones tell a story; they supply "links"; they
may help clothe the skeleton with flesh, but not with skin
color.
Our ancestral skin was probably dark. The amount of
pigment increased in the Negroid type, decreased in the
Mongoloid. They represent the two extremes. But "high"
and "low" skin color is as sound biology as grading planets
by color would be sound astronomy: Venus "highest" be-
cause whitest!
Kinky wooly hair is found in no apes or monkeys; straight
black hair is. The kink is the "highest" type, the straight
black the "lowest." Where shall we put the red — and the
tow-heads?
The African's jaws are heavy: they support a first-class
set of teeth. The European goes to the dentist to have his
jaws stretched; high — or merely degenerate? The Negro
scores with his thick out-turned lips; no men in the world
have such human lips as the blackest Africans. Thin lips
are primitive — "low," apish. Even in the bony ridges above
the eyes, most Negroes are among the "highest" of man.
This ridge is extraordinarily developed in the gorilla; also
among the blacks of Australia. But in the gorilla it is a
secondary sexual character. It is not found in gorilla
children, nor at all in gibbons of either sex.
The earliest human skulls were probably long. Negro
skulls are long, but not so long as the Eskimo. There are
round heads in Europe; rounder, in China. There is no
41
WHY WE BEHAVE LIKE HUMAN BEINGS
evidence that big brains are innately associated with long or
with round heads; nor any evidence that extreme artificial
deformation of infants' skulls (a widespread custom)
changes the size of the brain or the capacity for intelligent
behavior.
In brain weight, the average of a hundred Europeans would
slightly exceed the average of a hundred Africans, but
among the Africans many will be found exceeding the Euro-
pean average. The two groups overlap; no sharp line can
be drawn. Nor, after diligent search, has any difference
been found in brain structure or in convolutions. Intelli-
gence does not depend on size of skull, nor is a big skull any
proof of ability. Neanderthal man of fifty thousand years
ago had a bigger skull than we have; he disappeared.
The Negro's lumbar vertebrae are of a primitive type; his
gait is as upright as the European's. His spine retains
more of its original suppleness.
The Negro's nose is primitive ; it would not be so primitive
if he had less jaw. The more the jaws recede, the more
prominent the nose. If a low-bridge nose is "low," the
"highest" bridge comes from Asia, through the Jews, acquired
from the Hittites.
In long arms as compared with leg length, the African is
more primitive than the European; as he is in his longer
heel and smaller calves. In size and shape of external ear,
he is less primitive than the European.
What is it all about, then? Much of it, convictions; habits
of mind; prejudices, emotionally reinforced. There are
dozens, perhaps hundreds, of physical types. Some have
peculiarly or excessively marked features in one direction,
some in another. To have diverged from the parent type
means — simply divergence. We read significance into color
of skin and other physical traits without knowing the facts
behind these traits or the causes of change. There is no
known fact of human anatomy or physiology which implies
42
THE LIFE CYCLE AND THE HUMAN RACE
that capacity for culture or civilization or intelligence inheres
in this race or that type.
How about the "Nordics," then? How comes it that the
Anglo-Saxon is at the top of the heap? Is it not because of
his inherited ability that he rides the wave? The answer is
to be found in the cultural history of man. What wave did
the Anglo-Saxon ride in the days of Tut-ankh-Amen, or of
Caesar, or of William the Conqueror? Are his feet riveted
to the crest?
Civilization is young; blood is as old as salt water. Once
there was no Anglo-Saxon; but there was "civilization."
Were there "higher" and "lower" races then? How "low"
the savage European must have seemed to the Nile Valley
African, looking north from his pyramid of Cheops!
Divergence, mixture ; in isolated spots more divergence, less
mixture; and so, sharply defined types — as the Eskimo. No
people have a more distinct physical type than they have. I
know of no skull more specialized or more easily distinguish-
able in a collection of skulls than an Eskimo's. They are
"pure." Perhaps no people living are purer! No one pre-
tends that there is an Eskimo race.
"Pure" types are extreme types. Blue eyes, flaxen hair,
white skin, is an extreme type. The huge African with kinky
hair, black skin, thick lips, high smooth brow, hairless body,
is equally extreme. One is as pure as the other; one is as
high as the other.
Huxley classified man by hair; he was too good a zoologist
to classify cats by hair. Hair is only hair. Its color is one
thing, due to pigment; its shape is another. Straight hair
in cross section is round; kinky hair, flattish. There is
straight black hair, black hair that will not stay straight, and
curly hair from red to black.
We know too little yet what environmental change does to
physical structure, too little of the permanence of types, too
little of the causes of change of type. We have no classi-
fication of man based on stature, skin color, hair form, head
43
WHY WE BEHAVE LIKE HUMAN BEINGS
form, proportions of limbs, etc., so correlated that they fit
one race and one only. The original divisions of the human
race are not yet known. Possibly they never will be known;
possibly there were no grand divisions; possibly only minor
types developed from time to time. Some of these types
became extinct or left only traces which, through intermar-
riage, have become so hopelessly mixed that they can no
longer be distinguished.
Nature is not so prejudiced as we are. She says that there
is a human race, that all human beings are of the same
genus Homo, species sapiens. She draws no color line in the
human or in any other species. Black and white dogs mix as
readily as do blacks and whites when the sex impulse is not
outlawed, and are equally fertile.
In biology, fertility is generally regarded as a criterion of
species. Using "race" as S3nionymous with "species," man is
of one race. Hence the difficulty in distinguishing even sub-
species, subraces, varieties, and types of men; they overlap.
The human species has interbred. There are no biologically
pure varieties and certainly no pure races, except, possibly,
the Pygmy.
13
Open your atlas to a map of the world. Look at the
Indian Ocean: on the west, Africa; on the north, the three
great southern peninsulas of Asia; on the east, a chain of
great islands terminating in Australia. Wherever that Indian
Ocean touches land, it finds dark-skinned people with strongly
developed jaws, relatively long arms, and kinky or frizzly
hair. Call that the Indian Ocean or Negroid division of the
human race.
Now look at the Pacific Ocean: on the one side, the two
Americas; on the other, Asia. (Geographically, Europe is a
tail to the Asiatic kite.) The aboriginal population of the
Americas and of Asia north of its southern peninsula was a
44
THE LIFE CYCL5 AND THE HUMAN RACE
light-skinned people with straight hair, relatively short arms,
and a face without prominent jaws. Call that the Pacific
Ocean or Mongoloid division.
This grouping of man into two grand divisions was pro-
posed by Boas. The scheme has the merit of convenience
and is based on facts. Almost every shade of skin color can
be found in India. But the early inhabitants of India were
black. Their descendants survive to-day on many isolated
peaks of Central India. They have Negroid faces, dark
skin, woolly hair. In the Malay Peninsula and the Philippine
Islands are isolated bands of little blacks or Negritos. The
blacks have disappeared from Java, and in Sumatra have
left only a tinge. The natives of Australia are black, as
were those of Tasmania. The Melanesian Islands north of
Australia are, as their name implies, peopled with blacks.
Negroes did not get their skin pigment from any "mark"
put on Cain. Bible and biology are silent on Cain's color. ^
Biologically speaking, the white skins of North Europe havef
lost something. When or where they lost their pigment, and|
why they lost more than the Asiatics, we may never know.j
But they have lost enough, in Kroeber's opinion, to suggest
that to Boas's Negroid and Mongoloid divisions a third
should be added — the Caucasian.
Kroeber distinguishes four subtypes: Nordic, Alpine, and
Mediterranean in Europe, and Hindu in Asia. What are
the facts? In general, skin color deepens and stature dimin-
ishes in Europe from north to south. North Germans are
Nordic; South Germans, Alpine. Tjie Alpine is broad-
headed; the others, long. The Hindu is long-headed and
dark-skinned, probably due to mixture with the submerged
aborigines. Otherwise we have not moved a foot. It can
as easily be shown that between North Europe and India
there are only three subtypes — or that there are thirty-three.
[ You can have as many as you like. To use William James's
I figure, counting "subtypes" is as profitable as counting the
I stones on a New Hampshire farm. But if any Nordic's
45
WHY WE BEHAVE LIKE HUMAN BEINGS
pride is soothed by recognizing a Caucasian division and
four subtypes, let it be soothed.
The prevailing color of the Mongoloid type is yellow.
Malays and American Indians are nearest to the original
type. The Chinese are a divergent strain; the Eskimo, a
peculiar subvariety. The Negroid type abounds to-day in
Africa proper (south of the Sahara) and in Melanesia. |
Millions of Europeans are darker in color than millions i
of Asiatics. The colors overlap along the borders; they j
will intermarry. The border itself is a political boundary, j
not a racial barrier. North Europeans were not always
as colorless as they are now. Once there was neither Mon-
goloid nor Negroid. These divisions simply represent direc-
tions of development, probably begun on two continents — |
Asia, Africa. Some diverged from the main line before !
others; their affiliations cannot be made out.
For example, the Bushmen and Hottentots of South Africa !
are two distinct Negroid subtypes; yet they are also distinct j
from typical blacks. Both are yellowish in color, have long I
heads, short flat ears, short legs. Are they remnants? Of |
what? I
African Negroes and Melanesians of the South Pacific i
are close kin. The African has a flat nose, the Melanesian i
aquiline. Why is the Fijian black, his nearest neighbor i
yellow?
The Australian black is a puzzler. In some ways he is i
nearer Caucasian than Negroid. He is short, slender, long- j
headed; has a broad nose, wavy hair. His closest kin are i
the primitive folk of South Asia : Kolarians of India, Veddas i
of Ceylon, Sakai of the Malay Peninsula; the group is often i
called the Indo-Australian. Possibly the Veddas branched J
from the Caucasian type before it lost its pigment and took J
on the European type of face. |
The Negritos, or Pygmies, are even more puzzling. The S
average stature of the human race is five feet five inches, i
Few groups of men vary from this more than two inches. No i
46 j
THE LIFE CYCLE AND THE HUMAN RACE
race averages less than five feet or more than five feet ten
inches except the Pygmies of equatorial Africa, the Malay
Peninsula, New Guinea, and the Philippine Islands; they
are true dwarfs. Their average stature is a full foot short
of the average of that of man. Many adult Pygmies are
only four feet; no males exceed five feet. If stature were
held to be a mark of race, there would be only two races —
Pygmy; non-Pygmy.
The Pygmies are as black as blacks; they are dwarfs; other-
wise they are as human as Nordics. In jaws, lips, and nose,
they are more Nordic than African; in relative length of arm
to leg they are almost as close to the Chimpanzee as the true
Negro.
The Pygmies are spread around a quarter of the globe.
They are so alike in physical type that they constitute a real
thorn in unraveling the history of man's body. They com-
plicate the general problem of human races; they constitute
a distinct problem in themselves. Are they remnants, heritors
of the ape crowd that left the trees for good? Possibly.
Theirs, perhaps, is the type of body our ancestors tried out
ages ago. It was good enough to be human and to survive;
it was not good enough to subdue the earth.
Two points seem to stand out over and above every dis-
cussion of races and varieties of man: there are areas of
characterization — within such areas, especially if isolated
for long periods, certain physical traits or varieties become
pronounced; these physical traits or varieties are neither
necessarily biologically useful nor related to mental capacity
or intellectual endowment.
14
Unless well protected, or in rainless Peru or Egypt, or in
dry caves, or the cold storage of Arctic ice, or in oil, wax,
or amber, the body soon yields to the bacteria of decay or to
the teeth of wolves and hyenas. For bone or other tissue to
47
WHY WE BEHAVE LIKE HUMAN BEINGS
be replaced by mineral v/hereby it petrifies or "fossilizes,"
many conditions must be right. The wiser the animal, the
less likelihood of its being caught in quicksands or en-
gulfed by the gravel and silt of floods. Primitive man was
as little enamored as we are of being buried alive.
Fossil remains of the famous Cro-Magnon man have been
found in Wales, and especially in France. Possibly earth
never saw finer built human beings. His brain was 15 per
cent larger than ours, his stature taller than any living race
by two inches. He was clean-limbed, lithe, and swift. He
had a good chin, thick and strong jaws. His head was long,
his face broad. He buried his dead. He was an artist and
an artisan. He lived about 25,000 years ago. Did he be-
come an ordinary European, or did he disappear? No one
knows.
Beyond Cro-Magnon, our forbears rather run to brutish
casts. Grimaldi man was of the Negroid type. Neanderthal
man had a huge head, chipped flint, and buried his dead. He
is set down at 50,000 B. C. and left no known heirs. He
is the first known cave-man.
The jaw of Heidelberg man fits a gorilla, but the teeth
are ours. He is possibly 400,000 years old. Piltdown man
is possibly a hundred thousand years older. Some think he
was an ape. Some say he was the first Englishman. We have
reached a point in time where no one knows who's who.
The champion fossil is Pithecanthropus erectus (ape-man
erect), discovered by Dubois in Java in 1891. He is cer-
tainly a half -million years old; some say a million. He is
more pithecoid than any known human being, more anthro-
poid than any known ape. He was as erect and almost as
tall as the average European. He had definitely left the
"well-ventilated arboreal tenements." He was a low-browed
moron — and may be represented in the living flesh. But
whether he was of the direct line that led to man, or only of
a line that ended with himself, is not yet definitely known.
It is enormously significant that, after a debate lasting more
48
THE LIFE CYCLE AND THE HUMAN RACE
than a quarter of a century, the biologists of the world can-
not decide whether Pithecanthropus erectus belongs to the
first or the second of the earth's First Families. That makes
him a pretty good link that is no longer missing.
15
There are six families of Primates, premier order of
mammals: 1. Lemuridae (lemurs); 2. Hapalidae (marmo-
sets) ; 3. Cebidae (monkeys) ; 4. Cercopithecidae (baboons,
monkeys, etc. ) ; 5. Simiidae (manlike apes) ; 6. Hominidae
(men).
To import monkeys for their sex glands is ghastly busi-
ness, perhaps the lowest that has engaged the cupidity and
lust of man, but to shoot down simians as we do mad dogs or
boys in uniform is a crime. The four Anthropoid apes are
our next-of -kin-living; they should be respected as cousins
and not exterminated as vermin or Indians.
Man never was a gorilla, a chimpanzee, an orang, or a
gibbon. No biologist ever made such a claim. Whether these
apes could have developed into human beings is a different
story. They have the makings — all the parts. If we knew
how heredity works and could control variation, we might
breed from an ape a being that could dig a ditch, play the
piano, talk English, and sing the "Messiah." We can teach
them to smoke cigarettes, chew tobacco, drink beer, wear
clothes, and eat with a knife and fork. We do not yet
know the limit of their capacity to learn human ways.
Why do zoologists put these four apes so close behind us
that we can feel their breath and they can catch our dis-
eases? Because they are Anthropoid. Nothing has yet sur-
passed them in the race to become human. Their anatomy, em-
bryology, histology, morphology, paleontology, physiology,
and psychology entitle them to second place in the Ancient
and Honorable Order of Firsts.
They vary in their man-likeness; no one is in all ways
49
WHY WE BEHAVE LIKE HUMAN BEINGS
closest to man. The orang looks like an Irishman ; the gorilla
is built like Jack Dempsey; the chimpanzee is the most
angelic; tlie delicate gibbon has a lady-like skull and an up-
right carriage. The first three — ^the Great Apes — are the
extremes of variation from a generalized ancestor. The
gibbon varies least, and to that extent is nearest the tree
man climbed down when he decided to stand up and talk.
Except in teeth, the young female gorilla is the most
human. Her father is a brute in size and appearance. Only
five feet high, he may weigh over 400 pounds: mostly neck,
chest, and arms. If his legs were of human proportions, he
would stand over seven feet high. His hands and feet are
almost man's. His courage is unbounded, his strength pro-
digious. His humanoid skull has retreated behind enormous
jaws and beneath powerful ridges required to support the
muscles to work the jaws. He is the blackest Anthropoid ; his
skin is nearly black; his hair is coarse dark brown, whitening
with age.
The chimpanzee, like the gorilla, lives in jungle Africa.
Like the gorilla, he has a shuffle-along gait, swinging his
body between his long crutch-like arms. He has the gorilla's
proportions, but never the great bulk of chest. And so is
more at home in the trees, where he builds his nest, as does
the orang. The chimpanzee's skull is not unlike the one ape-
man erect tried on when turning into man — and gave up
because it had too much jaw for the teeth required and not
enough brain-box for ideas.
Our other two cousins are Asiatics. The larger is that red-
headed satire on the human race, the Wild Man of Borneo
and Sumatra; known to the natives as orang-utan, to science
as Simia satyrus. The orang is the original roundhead. He
is chunky, rather lazy, but has a good mind. He moves into
a new nest when he has eaten up all the figs and young leaves
in the neighborhood of the old one. With his four-foot body
and his seven-and-a-half -foot arm-spread, he can swing
50
THE LIFE CYCLE AND THE HUMAN RACE
through the forest faster than a man can run. He slows up
on the ground, where he is less at home.
The gibbon (Hylobates) is the prima donna of the Anthro-
poids. If our weightiest opera star could sing as loud in
proportion to size of body as can the slender three-foot-high
gibbon, she could drown the siren of the Leviathan.
There are several varieties of gibbon, marked chiefly by
hair and skin color. None is so dark as the African apes.
With arms relatively longer even than the orang's, they swing
across the forests of south-eastern Asia with amazing skill and
rapidity. For hours on end they clear fifteen-foot spaces;
as much as forty feet when in a hurry.
In shape of skull and character of teeth the gibbon is the
most primitive ape, and thereby the most humanoid and
nearest the source of man's origin. He walks erect, his
arms are free and straight, his brain-centers for touch and
hearing are humanoid. In other words, of our four first
cousins the gibbon has the closest speaking likeness to our
great-grandf ather.
The Cercopithecidae share with man and man-like apes the
doubtful honor of having thirty-two teeth, a narrow nose, a
tail more ornamental than useful, and a thumb which can
describe a circle. Their big toe is equally opposable, a
trait we generally leave in the cradle. They have no vermi-
form appendix; as compensation, they have callused rumps.
These, in mandrills, together with the cheeks, are gorgeously
colored; rarely are more brilliant blues, lilacs, and scarlets
found in nature.
The baboon is named Cynocephalus from his dog-like head.
He walks on all-fours, has long since abandoned tree life,
and is so strong and savage that he easily holds his own on
the ground. He has the meanest disposition, and, in spite of
fine fur, painted cheeks, and brilliant bottom, is the least
prepossessing of the Primates.
The macaques, of which the Barbary ape of Gibraltar is
the only Primate but man living in Europe in historic times,
51
WHY WE BEHAVE LIKE HUMAN BEINGS
are mostly Asiatic. One species lived in Japan, and is
preserved in inimitable art. In fact, never did contact be-
tween two First Families lead to such happy results as when
they posed for Japanese artists.
The two American First Families (2 and 3) are just
monkeys. They have broad flat noses, no cheek pouches or
callused rumps, tails generally prehensile, and a thumb often
tiny and never opposable.
The tiny marmosets are greatly prized by sailors, and, since
the opening of the Panama Canal, many spend their last
days aboard a warship. They have the same number of
teeth a sailor ought to have.
The Cebidae include all other New World monkeys. They
have thirty-six teeth, humanoid nails — flat, instead of claws —
and a tail as good as a fifth hand. The best known Cebida
is the capuchin, named from its monkish garb — often dis-
guised by the rags of his bondage to an Italian organ-grinder.
This contact between First Families may please the children,
but has not led to art. Probably a capuchin is no happier
on the East Side than is a marmoset on a flagship. Yet the
tiny marmoset has the brain of man at the third month of
fetal life.
The lemurs are our poorest relations — poorest in all that
makes for kinship between man and monkey. They live in
the trees, prowl around all night, sleep all day. Their body
resembles that of a four-footed animal. Their brain also
is of low type; the hemispheres of the fore brain are small
and do not cover the hind brain. Their second toe is a claw,
often weirdly long.
It is a far cry from man to lemurs, but the links yet
missing are not between man and the great apes, but between
the great apes and the gibbon and between the gibbon and
monkeys. In one sense the great apes are halfway between
man and gibbon, yet the gibbon is much closer to the three
than to monkeys. It is also related in many ways to the
New World monkeys. Hence it is likely that gibbon. Old
52
THE LIFE CYCLE AND THE HUMAN RACE
World monkeys, and New World monkeys all came from a
common stock. The New World monkeys developed in one
direction, the Old World monkeys in another. But while
the gibbon preserved and perfected its purely arboreal
mechanism, it also developed an upright posture and, when
on the ground, an upright gait. Orang, chimpanzee, and
gorilla also specialized, each in its own way. The gorilla
evolved the largest brain, but only larger than chimpanzee's
as its body is larger.
The gibbon, in common with the great apes, can be inocu-
lated with infectious diseases: syphilis, for example. Such
inoculation in monkeys leads only to slight disturbance.
Monkeys do not respond to the test for human blood, nor
do any other mammals except the four Anthropoids.
The common ancestral stock of man and Anthropoids de-
veloped in two directions: the gibbon remained small; the
others became heavy and partly took to the earth. Man
came from that group and left the trees altogether. But
even as he turned in our direction, his equipment was in-
valuable. His long sojourn in the tree-tops and his agility
in swinging through the forest were a great education, for,
as Lull says, "every hand-leap required that he instantly
solve a compound problem in mathematics made up of dis-
tance, trajectory, direction, and strength of limb." When
he did not solve that problem, he crashed! Mental prepared-
ness had a high premium in those days.
We often wonder where we get our brain; it was stand-
ardized a million years ago. From stock such as the gibbon,
man also sprang. That life in the trees gave him his start
toward his big brain. There was no "fall"; man climbed
down. And that is a story of changing limbs.
16
There is nothing in man's arm, from the muscles by which
it is fastened to his head, neck, and spine, to his finger nails,
53
WHY WE BEHAVE LIKE HUMAN BEINGS
that does not show modification due to change in function
since man left the trees. The gibbon line started the changes.
He can stand as straight as man; his shoulders have already
swung around to the side of his body, his thorax begins to
assume the human type.
Our ancestor needed a long forearm and a short upper
arm. In swinging through the trees the body, attached to
the lever at the shoulder, is the weight; the fulcrum is in the
elbow; the biceps muscle furnishes the power to the moving
lever or upper arm. The greater the distance of this lever
from the fulcrum, the greater the power. The biceps muscle
in the gibbon has extra heads of insertion, the better to lift the
greater weight.
Our ancestral arm became modified to meet a change in oc-
cupation. With hand work, the movable lever was no longer
the upper but the forearm. Men vary greatly in relative
length of upper to forearm, but in general our forearm is
short and powerful. We do not need the extra heads of inser-
tion for our biceps, but one man in ten still has them.
Why did not man fly down? That would have been
speedier. In a pinch he could fly up again. To fly is to be
free. Bats can fly. They are high mammals; they are marvel-
ously free. But at what a price! They lost their hands. They
cannot handle things. A baby can; does. That handling of
things is a priceless possession, worth more than eagle's
wings. With hands the baby brings things up to its eyes,
ears, nose, mouth; turns things over, examines them from
all sides; prods things to see if they are alive; shakes them
to learn if they are hollow; feels them to find out if they
are ripe or rotten or hard or smooth or hot; feels its own
body, explores itself.
The monkey is no less handy, rather more so; and mar-
velously quick. The hand of a baboon in a Calcutta zoo shot
over a high wire screen and picked my spectacles from my
eyes ; I knew he had them only when I saw them in his hands.
He twisted the wires into a shapeless mess and broke the
54
THE LIFE CYCLE AND THE HUMAN RACE
lenses into tiny bits; nor gave me revenge by cutting his
fingers.
It is enormously significant that a normal newborn can
hang by its hands for half a minute; three weeks later, for
two or possibly three minutes. Not so much? Try it. An
average three-weeks-old baby can outhang an average thirty-
year-old parent. It is a doting father that encourages baby
to get its fingers in his beard; it "hangs on for dear life."
So it does. It had to, once, or fall. That was the way it
clung to home and mother up a tree.
Primitive peoples to-day walk up and down trees, "like
a monkey." Some tribes make their homes in trees. Arm-
less men can learn to write and shave with their toes.
When a boy drops from a limb, his legs bend out at the
knee and hip joints. When he falls, he generally breaks
something. The legs and feet of a newborn babe are no
good at all for walking on a flat surface. The legs are
crooked, the feet turn in. When it can walk, it does not
walk on the soles of its feet, but on the outer rim of the
soles. The bones under that outer rim are the first to appear
in fetal life. The baby can wriggle its big toe almost as
much as its thumb. Its drawn-up crooked leg, inturned foot,
and opposable toe are lingering mementoes of the days when
our feet were more at home on the limb of a tree than on
the ground. Our hand is very wonderful, but not so "human"
as our foot.
Even our ancestral backbone was almost human. It was
not arched, as is the dog's; it was already a column. Not
for months can the baby stand up, but it can soon sit up.
Man sat up on a limb before he stood up on the earth. If we
must "point with pride" to some part of our anatomy denied
our monkey ancestor, it is not to our spine or to our hand, but
to our foot. To become human, the foot had to travel as
far as our brain. Yet we hide it in a shoe made on the
toe formula of a spider monkey. Our longest toe is our
big toe; if not, our foot is a throw-back and a poor relation.
55
WHY WE BEHAVE LIKE HUMAN BEINGS
The human foot at best is a misfit and is not improved by
being shod. By the time we have lost our lower jaw through
disuse, we shall have lost all our toes but the big one. Our
foot will then be as highly specialized as a horse's. Of all the
Primates, man's foot is the most primitive; next is the go-
rilla's. Even Pithecanthropus is allowed a human foot be-
cause his thigh bone was so human. He walked like a man
— and as man cannot at birth.
The great apes' babies also have short and crooked legs,
and, like man babies, but unlike monkey babies, cannot
hang on to their mothers by their fingers and toes. Their
fingers are only fair graspers and their toes worse; their
mothers' bodies have not enough hair to hang on to. They
must be carried. On that fact rests the foundation of every
human home. The first kindergarten of human conduct was
in the trees.
A monkey baby clings to the hair of its mother's body by
its fingers and toes. Lemur babies wrap their legs around
their mother's body, cling with their arms, and anchor them-
selves by holding on with their mouth to one of the two extra
teats in her loins.
Our ancestor neither fell nor dropped from the ancestral
tree. He walked down; his brain had become too big for
foliage. It was the most important step in the life of the
human race. His debut as a terrestrial mammal, with noth-
ing but his wits as his principal weapon, was the culminating
episode in the drama of life on this planet. It was ages be-
fore he became a good actor, but without his schooling in
the trees he could hardly have become human in a million
years.
17
Man lost his tail and began to acquire his present stature
and upright gait, including a tendency to hernia, during an
56
THE LIFE CYCLE AND THE HUMAN RACE
arboreal existence in the Miocene epoch of the Tertiary era
from two to three million years ago. During the last million
years there has been little change in his stature or size of
body. In weight and length of trunk and head, the chim-
panzee is as human as we are. The greatest change was
in larger head, shorter jaws, shorter body and arms, longer
legs.
During the Miocene, New World monkeys became differ-
entiated from lemurs and from the tailed monkeys of the
Old World. Small tailless apes not unlike the gibbon had
evolved from the Old World monkeys. This was a big step
in man's journey up off his belly. Through the ancestor of
modern gibbons, man lost his tail and gained his gait.
Dryopithecus, first of the big-bodied apes which eventually
led to man, also appeared during the Miocene. He is a pre-
Homo. His line is quite as important as that of Charlemagne
or the Mayflower. It divided. One branch is represented
by the extinct Paleopithecus of India and the modern great
apes. The other branch took to the earth; from it came
Pithecanthropus, Piltdown, and Heidelberg man. But a mil-
lion years elapsed before any ape became so human that he
could only be Homo.
Was it speech that made man? Speech often leads to his
downfall, and in all the world is no mechanism so delicately
poised as a woman's tongue. But vocal cords are as old as
frogs; and few of us can chatter like a magpie or a monkey.
Nor can we howl like a howler-monkey or scream like a
gibbon. Fossil men left no voices, nor anything to suggest
the nature of their larynx. Yet it is significant that the
normal human larynx has no such laryngeal pouch reso-
nators as have many Primates. Man has had to make an
amplifier. But no ape has developed speech into such a
perfect medium of communication as man. This is not
alone due to any imperfection in voice mechanism.
Was man's appearance due to his big brain? The brain
57
WHY WE BEHAVE LIKE HUMAN BEINGS
weight of a tuna fish compared to its body weight is as 1 to
37,000; of an ostrich, 1 to 1,200; of a horse, 1 to 500; of a
frog, 1 to 170; of a gorilla, 1 to 120; of a lemur, 1 to 40; of
man, 1 to 35. But brain weight to body weight in rat and
magpie is as 1 to 28; in marmoset, 1 to 22; in capuchin, 1
to 13. The place of honor goes to the humming-bird, 1 to 12.
Imagine a human being with a brain as large in proportion
to his body as has a humming-bird!
But in weight of brain in proportion to weight of spinal
cord, man exceeds all creation: 50 to 1; in the gorilla, it is
20 to 1; in mammals below Primates, 5 to 1; in birds, be-
tween 10 and 2 to 1; in fishes, 1 to 1. Spinal cord is good,
but brains are brains. And there is nothing in the world
like them.
Longevity among Primates began with the great apes. If
adolescence ends with a full set of teeth, adult life in man
begins at twenty-two, in the great apes at fourteen. Keith
holds that man's age at sixty-six is equivalent to that of the
gibbon at eighteen, of the great apes at forty-two; and that
a native Australian of forty-two shows the age changes of
a European of sixty-two.
There are no marked sexual differences among gibbons;
as a rule, the female is a bit heavier. In the chimpanzee,
sexual differences are about the same as in man. Orangs
and gorillas show marked differences, the gorilla especially.
The male is larger, heavier, stronger; his jaws and teeth, es-
pecially the canines, are more powerful. He is the fighter.
Secondary sexual characters in man thus appear to be
only one or two million years old. They seem to be dimin-
ishing. Nature gets rid of useless structures or finds new
functions for them. Modern woman shows no great disposi-
tion to find any new function for them.
Europe or Asia? Hrdlicka says Europe — through Pilt-
down man to Dryopithecus, the Miocene ape. Osborn says
Asia: "Asia is near a center of evolution of a higher Primate;
there we may look for the ancestors not only of prehuman
58
THE LIFE CYCLE AND THE HUMAN RACE
stages like the Pithecanthropus, but of higher and truly-
human types."
In that case, prehistoric man in Europe was an immigrant
from Asia, as was prehistoric man in America. Possibly
Asia, in a not too remote age, will lead the race to be more
humane.
59
CHAPTER II
THE EVOLUTION OF THE EARTH, LIFE, AND SEX
1. Life's Genealogic Time-table. 2. The Hand That Rocks the Cradle.
3. Experiments in Brains. 4. New Styles in Eggs and Incubators. 5. Our
Indebtedness to Fish. 6. Back to the Lifeless Earth. 7. The Start from the
Sun. 8. The L M N's of Nature. 9. The Fitness of Water and Carbon
Dioxide. 10. The Evolution of the Organic. 11. Darwin and Natural
Selection. 12. Lamarck and Acquired Characters. 13. The Nature and
Evolution of Sex. 14. The Colored Bodies of the Egg. 15. The Great Game
of Heredity. 16. Eugenics, or Being Well Bred.
1
The race to be human began with the first living being.
That being was possible because the earth brought from the
sun some very remarkable elements and because the sun
continued to shine. Under its beneficent rays, certain ele-
ments became so dynamically constituted that they began to
perform like an organic individual. It could do what matter
had not done before, behave like a living being. It grew,
but its size was limited by its nature, as is that of a raindrop
or a drop of oil or a piece of jelly. It split up. It developed
new ways of growth, and evolved sex. Various theories have
been proposed as to how all this came about; even propa-
ganda for taking the future of the race in our own hands.
These are to be our concern in this chapter. A time-table
of life will start us off". With that before us, we can soon
trace our body back to a bacterium or something just as
good. It is a long journey, but we shall try to keep out of
blind alleys from which there is no return. Meanwhile, do
not forget that the egg with which we begin life has been
living since life began; that egg has had a long history and
60
THE GEOLOGIC TIME-TABLE OF ANIMAL LIFE
(Modified from Organic Evolution, by Richard Swan Lull, 1921,
by permission of the author and the pubhshers, The Macmillan
Company.)
Era
Ennph or
x-jyjyjyji-i. yji.
Period
Advances
Years'
Duration
Psychozoic
Age of Man
Recent
Civilization
25,000
Cenozoic
Age of
Mammals
(Ice Age)
Pleistocene
End of great mammals
9,000,000
(Matthew)
60,000,000
(Barrell)
Pliocene
Man-ape became Man
Miocene
Culmination of mammals
Oligocene
Higher mammals
Eocene
End of archaic mam-
mals
Mesozoic
Age of
Reptiles
Archaic mammals
40,000,000
(Matthew)
160,000,000
(Barrell)
Cretaceous
End of great reptiles
Jurassic
Birds
Triassic
Dinosaurs
Paleozoic
Age of
r isnes
y^aX JJUllllcl
ous
End of ancient life
30,000,000
(Schuchert)
700,000,000
(Barrell)
Land vertebrates
Primitive reptiles
Ancient sharks
Devonian
Amphibians
Silurian
Lung fishes
Ordovician
Armored fishes
Cambrian
Shellfish
Proterozoic
First invertebrates
500,000,000
to
1,000,000,000
(Barrell)
Archeozoic
Unicellular life
61
WHY WE BEHAVE LIKE HUMAN BEINGS
has learned much about life. Otherwise we could not learn
to behave like human beings in so short a time.
Our most human parts — brain, skull, teeth, voice organs,
upright gait, and fingers — are not new, they are not unique,
they are not ours exclusively; for life itself they are not
even essential. Some human beings never use their brains,
their skull is merely a frame for features, they lose all their
teeth, and their fingers are all thumbs. No, our most human-
oid parts will not give us much clue to the nature of the
ceaselessly changing creature that became at last human.
A man, monkey, opossum, lizard, frog, shark, flea, fish-
worm, oyster, and malaria germ have one thing in common:
they must eat and breathe, or die. Every animal must have
lungs and stomach, or the equivalent. Call it viscera. Viscera
are vitals, the something without which there is no living
animal. What else have they in common? A motor mechan-
ism to bring the necessary elements of life within reach of
the living body's vitals.
The great difference between man and oyster is not viscera,
but motor mechanism. That difference is so great that man
can catch the oyster and eat it. The most the oyster could
catch of man is a finger, and then only if man carries his
finger to the oyster and invites the oyster to catch it. Even
then the oyster could not eat the finger. The motor mechan-
ism of man and higher animals is knit together by a nervous
system, supplemented by vocal organs and presided over by
a brain.
The history of our body is primarily that of the mechanism
for getting food, ways of avoiding being eaten as food, and
method of growth. In other words, the chemical activities
whereby living beings maintain life are fundamentally the
same in all animals, but the laboratory in which these activ-
ities take place and the mechanisms for carrying the labora-
tory about and for acquiring information as to food, enemies,
etc., vary enormously.
Even our Primate ancestor up a tree lacked no parts to
62
THE EVOLUTION OF THE EARTH, LIFE, AND SEX
become human; certain parts merely had to be altered. Say,
two million years. Beyond these two, other millions passed
while body and brain bided their time; the earth was not
yet quite ready for nature's great experiment.
As Bergson puts it: "Man only realized himself by aban-
doning a part of himself on the way; he was not yet ready
to fight for his life with his mere wits." Wits are his greatest
weapon.
We must not think of our body as the most or the best this
or that. In many ways the eagle has a more specialized struc-
ture; it excels in eyesight, respiratory system, skeleton, and
locomotion. Even the bee in its own line, as Thomson says,
is hardly inferior to man and represents an achievement that
angels might desire to look into.
Life has tried out countless bodies. Certain species of
snails and Crustacea have survived almost unchanged from
pre-Cambrian days, sixty million years ago. Two-million-
year-old fossil ants embalmed in amber are so much like
ants of to-day that, could they awake from their sleep, they
could recognize their descendants, if their noses were not
stopped up. They kept to the middle of the road. That
man evolved from a lowly Primate means that the Primate
itself was neither an accident nor a highbrow, that it was
not too far removed from the body its ancestor brought up
out of the mud on to the dry land.
Many families of Nature's masterpieces have no living
representative because they over-specialized; they gave up
so much to tusk, trunk, canine, wing, leg, stomach, size,
height, length, or armor, that they had not enough to live
on. They put all their eggs in one basket. Earth's crust
is full of these fancy forms, so specialized they could not
meet change. Man got ahead because he could grasp an
idea, could talk it over with his fellow-men and think up
new ideas. The amazing thing is not that he became human,
but that he can be so inhuman in so many ways.
The fundamentals of living remained unchanged through
63
WHY WE BEHAVE LIKE HUMAN BEINGS
vast periods of time, the structure in which vital processes
functioned kept changing. When the larder shifted or the
nature of its contents changed, the method of keeping the
viscera in touch with the larder, or in preparing food so that
the viscera could digest it, had to change. Countless animals
still solve the problems of life with simple structures. Few
went in for brains. None but man ever tried to discover the
nature of brains or thought of preserving them in alcohol.
He could do this because the body he inherited could be
adapted to diverse occupations.
Reading the time-table backward suggests a parallel proc-
ess which seems to have been at work in human culture:
progress by leaps; between, long pauses. The pauses grow
shorter as time moves on.
For a hundred thousand years man gets along without
steam-control. The steam engine is invented. In the twink-
ling of an eye steamships plow the seas and every land is
ribbed with shining rails. The Age of Steam blossomed
out of nothing. Gossip formerly passed from mouth to ear;
at breakfast, now. Cape Town reads of the color of the hair
of the girl the Prince of Wales danced with the night before
on Long Island. This is another New Age.
How did man get along without radio, newspaper, steel,
steam, plumbing, arch, calendar, spear, flint knife, fire? He
did. But he gets along faster with them. So with life itself.
It got along without mammary glands and internal incubators,
skull and vertebral column, head and tail, brains. But with
brains, head, backbone, and placenta, the procession speeded
up, life shot out in new directions.
Progress is often made by lying low; let the other fellow
try out Nature's new-fangled notions. By holding out, man
came on the stage during the big scene. When the call went
forth for clever people who could double, shifty people who
could walk back to town if the show "blew," who could catch
and fry their own fish in case of need, who could dig out,
swim across, climb up and jump down, who were handy
64
THE EVOLUTION OF THE EARTH, LIFE, AND SEX
with their hands, had good memories and could mix, man
appeared.
All this took brains: a big brain, a brain so big it had to
wrinkle or burst its case; a brain with frontal lobes so big
they dwarf the hind-brain. A brain big in every way; in
absolute size and weight, in proportion to spinal cord, in
proportion to body.
Think of a jellyfish, a shark, or an elephant with a human
brain. The jellyfish has no head to put it in; the shark, no
bony skull to protect it; the elephant, no hands to do its
bidding. The human brain would be an incumbrance to the
jellyfish, a nuisance to the shark, and would drive the elephant
crazy.
Nature has made many extraordinary experiments. Some
survive: their parts had "survival" value; most of them dis-
appeared. But no great group-experiment was a total failure.
Even the Cyclops-eyed reptile of pre-Tertiary times survives
in the Sphenodon of New Zealand. The eye itself, as eye,
was a failure; we inherit it as endocrine gland!
2
If the hand that rocks the cradle is the hand that rules the
world, it will not hurt good government if the hand knows
what it rocks; or what the hand came from; or that the first
cradle was in a tree-top. The human brain and throat made
civilization possible, but it was the hand that built the home,
kindled the fire, and made human culture. There are simpler
and surer feet than man's, but none has carried such price-
less freight or been shod with the wings of a Perseus. The
human hand should build a monument to the human foot, for
the foot freed the hand!
In a class on Christian Evidences, the President of the
college wiggled his thumb and said, triumphantly, "No
monkey ever lived that could do that!" Could if it wanted
to. Watch a monkey climb a rope : thumb on one side, fingers
65
WHY WE BEHAVE LIKE HUMAN BEINGS
on the other. Sally, the chimpanzee, grasps the neck of a
bottle like a man, and opens a clam shell with the thumbs of
her two hands. Watch a monkey on a still hunt through the
hair of its mate.
Opposability of thumb is no marvel. The marvel is that
an organ modified for grasping limbs can also pick up a
pin, throw a stone, wring a chicken's neck, and crack a nut
with a rock. Any average monkey has a pair of such marvels.
The fact is that if a primitive five-toed foot had not been
carried into a tree and there developed along lines of its
original pattern, there would be no human hand to grasp
to-day. It was figuratively and literally kept in the air.
Had it specialized either as grasper or as support, it could
not have been turned into the marvelous organ that it is.
The monkey was not the only mammal that took to trees;
the whole marsupial family started their career there. The
kangaroo came down; his prehensile forefoot lost its offset
great toe. The koala remained; his forefoot developed an
opposable thumb and an opposable first finger. No vine is
a better dinger. When you shoot a koala you climb the
tree and pry its fingers loose or it will hang there till it rots.
Tree-sloths (cousins to armadillos) also specialized in grasp-
ing organs. One has only three fingers, each armed witli
hook-like claws; its hooks also hang on after death. Our
ancestors were adapted to an arboreal life; they were not
enslaved by it.
Some Primates experimented in fingers. A lemur lost
his second finger to give the thumb more grasping space.
Some tried claws instead of nails. The marmoset has a
thumb nail, the other fingers have curved, pointed claws. As
Primates progressed, nails replaced claws and all five fingers
were put to use. With the gibbon, the prehensile hand was
well developed. Early lemurs lived on rather than in the
tree-tops. The gibbon does not walk on trees, but swings
from limb to limb. Its hand is more specialized than ours,
66
THE EVOLUTION OF THE EARTH, LIFE, AND SEX
farther evolved from the ancestral type. The orang's thumb
is almost gone; often has no nail.
Several animals tried out the prehensile tail: chameleons,
opossums, an ant-eater, and some New World monkeys. Old
World monkeys were wiser. The spider monkey's marvelous
tail cost him two thumbs; in gaining a "fifth hand" his true
hands lost their perfection.
Invertebrates are allowed as many legs as they please up
to a millipede. The vertebrate limit is four, two pairs. They
began with fishes: gills modified for propulsion. Their
limbs are oars; the tail is rudder and sculling oar. When
fish crawled out of the water on their belly, their limbs
were paddles — as are ours in fetal life. Many vertebrates
kept on crawling on their bellies, and, like most snakes, lost
their paddles. Whales went back to water and turned their
front legs into oars again; they lost their hind-limbs.
Man never was a whale or a snake; nor did he ever walk
like a horse. He did not go in for stability, as did the horse,
cow, and elephant; mobility was his goal. In bones, muscles,
and plan, our forelimb is closer to a frog's than to a cow's.
It is built on the old fish type handed on by amphibians to
reptiles. Compared with the front foot of a horse, our hand
is primitive and ancient, closer to the hand of an extinct
iguanadon of Jurassic-Cretaceous times.
With that type of limb the first Primates climbed a tree.
It was a four-piece arm: humerus, swinging free at the side
and held against the shoulder-blade, which in turn was held
out and away from the body by the collar-bone acting as a
strut; forearm of radius and ulna, making possible the right-
side-up, upside-down hand movements; wrist joint of eight
bones; five fingers. These bones can all be matched in the
"hand" of a mud turtle, but not in the forefoot of a horse.
The turtle's wrist has one more bone, the central. All men,
gorillas, and chimpanzees have it in the fetal hand. It then
incorporates with the scaphoid bone. It sometimes forgets to
incorporate.
67
WHY WE BEHAVE LIKE HUMAN BEINGS
When our ancestor walked down the tree, his f orelimb was
already an arm and a hand; the tree had saved it from a
leg's fate. His hand could grasp the ball; his arm could
"wind" it up, as does the pitcher before he puts it over. It
did not have far to go to become the hand that rocks the
cradle.
A large litter is wasted energy without a suitable nursery.
The horse specialized in grass-cutting teeth and fast legs.
It has no nursery; the colt can run the day it is born. It must,
or the wolves will get it. Our Primate mother had no
natural nursery, but she had a natural clinging disposition —
as had her baby. As brain and body developed, the baby's
dependence on its mother became more profound. Apes
carry their young in their arms, as does man. Even a young
gibbon is dependent on its mother for seven or eight months;
she carries it to the water, bathes it, dries it. A gorilla
mother boxes her young hopeful's ears, and the male guides
and guards all his children.
Interpret all this in terms of pa, ma, and the baby. The
family grows larger. Family circle. Divided cares, mutual
responsibility. Human behavior began up there.
The tree-living Marsupial carries her young in a pouch:
a marvelous contrivance, a wonder-work of nature. The
tree-living Primate carries hers in her lap. She had to sit
up: she had to have a columnar instead of an arched spine;
hips to hold viscera; head poised at one end of the spine for
better control; chest flattened to agree with the columnar
spine; diaphragm shifted in position and moorings to con-
form to the new style of breathing; muscles once needed for
breathing now used to hang the arms at the sides of the body
and swing them out from the body.
Such were some of the changes required before the primi-
tive mammal that climbed the tree could walk down and con-
quer the earth. But not until earth became man's home did
his trunk reach hour-glass form. Then it was that the
mammae took on well-developed nipples and their encircling
68
THE EVOLUTION OF THE EARTH, LIFE, AND SEX
areola. But as Woods Jones says, something more subtle
than mere change in bone and muscle was involved in man's
evolution. The kind of life lived through the ages up the
tree made possible the kind of wits needed to live at the
foot of it. There were no baby-farms or homes for children
of missionaries-abroad or officers-absent-on-foreign-duty, in
Miocene times; "mother love" was more necessary then for
the lives of young apes than it is to-day for their descendants.
3
In twenty million years the Age of Reptiles produced eight-
een orders. Five survive; too much specialization. Osborn
named one Tyrannosaurus rex. That saurian king was forty-
seven feet long, twenty feet high, heavier than an elephant.
His teeth were half a foot long; his feet were armed with
mighty claws. He was a perfect machine: in speed, size,
power, and ferocity, the most destructive engine that ever
lived!
He is an also-ran. Inside his thirty-six cubic feet of skull-
box he had less than a pound of brains!
The big-bodied pin-headed Reptiles were gigantic failures,
as were the first mammals nature experimented with. Both
turned to rock and left no descendants to mourn their loss.
And yet they had had everything conceivable in dental
weapons and heavy armor. Not enough brains!
With Oligocene times began another series of mammals;
more brains in proportion to body. Nearly all of them are
alive to-day. It was man's salvation to have had a tree-
climbing ancestor at that time.
Early land vertebrates smelled their way through life;
foods, friends, mates, all through the ends of their noses.
Like a dog. The scent was lost in the trees; also the need
for a long-drawn-out face, like a horse's, an ant-eater's, or
an elephant's. Monkeys do not touch things with their snout,
69
WHY WE BEHAVE LIKE HUMAN BEINGS
but with their finger tips, which are as good as most animals'
tongues for feeling things out.
Sight is much more valuable than smell. Having no need
for snouts, Primates shortened their faces. Having little need
for feet, they developed their hands. Hands could bring
things up to the eyes. Eyes could settle down where they
would be handiest. The eyes moved on to the front of the
face. Each eye sees an independent picture, but the pictures
overlap; the eyes can correlate and blend them into one.
Thus, Primates' eyes are binoculars with stereoscopic effect.
Many mammals have no such binoculars.
What can an elephant know of its body? It can feel very
little of it, see even less. WTiat does a monkey not know of
its body? What its hands feel, its eyes can picture. The
brain knows nothing of muscles, but it becomes a store-
house of pictured movements.
And so man's headpiece became a compact, snug affair;
eyes, ears, nose, tongue, teeth, all close together, easily
turned this way or that. With two, sometimes four, hands
available to bring things close. The brain grew as its re-
quirements grew. The motor mechanism of the body kept
improving; more brain needed to work it. The more it was
worked, the better it grew. Its areas of association between
hearing and seeing, seeing and touching, etc., kept on grow-
ing. These areas are the distinguishing features of man's
brain.
If man had received no more than mere bodily form from
his monkey ancestor, he might as well have had an opossum
for an ancestor. It was not mere body that made monkeys
smart; nor their brain that produced their hand. Their brain
made the most of their hand, but, as Jones says, while man
can play the violin because he has a big brain, what could
his brain do if his hand were a horse's foot?
Man's ancestor won his freedom not so much by special-
ization as because he kept his plasticity, extended his wits,
and improved his control.
70
THE EVOLUTION OF THE EARTH, LIFE, AND SEX
4
Eocene times knew nothing of tabloid foods and nature
herself was the dentist. No teeth, no food; no food, no life.
Instead of a knife, the primitive Primate used its incisors;
instead of meat-chopper or mortar and pestle, its molars. It
stabbed its prey with its hand, but kept the big canine to
show what it could do when angry. It saved its teeth by
using them. They were not good for anything in particular;
they were good enough for almost everything in nature's
larder. Our teeth are among the most primitive of all
mammals. Our four-cusped molars are more like those of
extinct Eocene mammals than they are like those of living
apes. We are the shortest-snouted Primate; our teeth, alone
of Primates, are in one continuous series. There is a real
gap between canine and incisors in apes; also in our milk
set — or should be, shorter jaws are lessening the gap.
Our ancestral Primate was a small, warm-blooded, primi-
tive mammal with forty-four teeth, four short legs all alike,
and feet with five toes armed with claws. It lived on insects,
worms, fruit, and nuts. \^Tio was its ancestor? How did it
become viviparous? Where did it get its mammae?
Circumstantial evidence points to a dog-toothed, low-
browed, Triassic reptile, called Cynodont. He is older than
the giant reptiles which appeared millions of years later,
lower than the reptiles which led to dinosaurs, which in
turn led to crocodiles and birds. If not the Cynodonts, then
we must assume that mammals started in the Permian period.
Some say it w^as in Africa, but probably Central Asia will
prove to be the birthplace of reptiles and mammals.
The reptile that developed into mammal had teeth fit for
a mixed diet. It could run, making possible a broader out-
look and a surer hold on life. Legs that lifted the belly from
the ground made warm blood possible. Warm blood made
energy more easily available and personal incubation of the
egg possible. And there is no more interesting tale in the
71
WHY WE BEHAVE LIKE HUMAN BEINGS
book of nature than the one which recounts her experiments
in eggs.
Mammals get their name from their mammae or milk-
glands. All mammals suckle their young, although true
teats appear only with marsupials, the second order of
mammals. Monotremes, the lowest mammals, lay eggs, as do
all birds, amphibians, fishes, and most reptiles.
But there is a vast difference between monotreme, bird,
and reptile eggs, and amphibian and fish eggs. The latter
are laid in water; they develop in water. Amphibian eggs
develop into tadpoles which live like fish; by and by their
gills close, their tails are absorbed, their fins become legs;
they hop up frogs or toads. But frogs can no more live
all their life under water than can whales or porpoises: they
must come up for air. Amphibians lead double lives.
As do some men. But our fetal gill-clefts never break
through. We can thank our reptile ancestor for that. Nor
do reptiles or birds have gill-breathing apparatus. Their
young do not metamorphose from a larval stage. The alli-
gator deposits her eggs in dry ground; if deposited in water
the eggs would "drown," as would birds' eggs.
Reptiles, ancestors of birds and mammals, invented a
new style of egg to get away from the double life led by
amphibians. All eggs are complex, but this reptilian egg
was the first to have a shell or protective envelope, and a
yolk inside: food to tide the embryo over the first stage of
life, oxygen until it grows a lung.
The embryo develops an amnion, or protective membrane
of two layers; between, amniotic fluid — storm-door and shock-
absorber. Also a second membrane, the sac-like allantois.
This is connected with the embryo's blood vessels; it is the
embryo's "lung." Oxygen, entering through the pores of
the eggshell, is picked up by the allantois and carried to the
embryo; the returning blood-stream carries carbon dioxide.
The egg must have air or the embryo within is asphyxiated.
72
THE EVOLUTION OF THE EARTH, LIFE, AND SEX
As the yolk-sac diminishes, the allantois grows in size and
efficiency.
Certain snakes and all mammals except monotremes are
viviparous: their young are born alive. What has happened?
The egg is incubated within the maternal body. The lung-like
allantois becomes placenta and unbilical cord. The placenta
grows fast to the wall of the mother's uterus. Through the
connecting umbilicus the embryo gets oxygen and nutrition.
Yolk — as in birds' eggs — is not needed. But nature is per-
sistent; the human embryo has a yolk-sac, but no yolk.
This vade mecum incubator is a great advance over the
reptilian way of letting the sun do it. But reptiles get the
credit for the new-style eggs. They were nature's answer to
a drought. That drought gave reptiles their great start. Those
that developed blunt dagger-like teeth into grinders with
cusps, and eggs that could hatch in a desert, were the reptiles
that led to mammals and man — and made valuable contribu-
tions to science.
Our indebtedness to reptiles, then, is very great: our ante-
natal robes, four-chambered heart, and a rising temperature
leading to warm blood. Some even go so far as to credit
a certain reptile with our ideas of the Tree of Knowledge.
Our family life was founded in the trees; but it is rooted in
the placenta. The long and intimate commingling of parent
and fetus had far-reaching consequences. The first placenta
was developed in the reptilian ancestor. By the time that
reptile had become mammal, it had warm blood, a hairy
body, and a muscular diaphragm between lungs and liver.
5
Reptiles developed the habit of living on dry land. An
amphibian pointed the way, in the Upper Carboniferous
Age. The family name of that amphibian is Stegocephalia —
because he had a roof over his head. He may date from
the Devonian period. He was heavily armored, and a flesh-
73
WHY WE BEHAVE LIKE HUMAN BEINGS
eater. His four limbs were well developed for crawling;
his bones, in number and character, were of the type that
millions of years later developed into the prehensile hands
and feet of Primates. He retained enough of his fish habits
to compel his return to water to deposit the eggs. In the
water the young developed.
To that amphibian ancestor we are indebted for four price-
less possessions: fingers and toes, true lungs, a wagging
tongue, vocal cords. The bullfrog inherits his voice direct,
nor is there evidence that he has improved it. It is known
that he puts it to the use it had from the start — a mate-call.
A vocal mate-call could have been of no use under water;
in swampy lands it was a necessity.
Beyond, and older than amphibians, are fishes. Our debt
to them is greatest of all: skull, at first a rude brain-box of
gristle; true jaws; limbs supported by bones articulating
with an axial skeleton. Such parts distinguish us from
devil-fish, oysters, clams, barnacles, and fleas. With such
parts, nature began to branch out on new lines; new lines
had something to go on. They could develop brain, the
skull protected it; a real spinal cord, the backbone carried
it. With skeleton inside instead of outside the body, and of
bone instead of shell, they could develop big strong bodies.
With their paired limbs they could travel, explore, experi-
ment. With their new type of mental machinery, they could
record new experiences.
What an amazing tribute to the persistence of nature! Every
normal human embryo develops a notochord. That notochord
is the oldest and only original "backbone," the only back-
bone to-day of the amphioxus or lancelet, possibly the only
living representative in direct line of the inventor of the
vertebrate idea.
From Cambrian days, when the first notochord was laid
in the first fish, possibly a half -billion years were to roll
from the scroll of life before man was to puzzle his brain
to discover the nature of the creature that decided it would
74
THE EVOLUTION OF THE EARTH, LIFE, AND SEX
be easier to carry its skeleton inside its body than on its
shoulders.
That creature is not yet known. Countless tons of rock
weigh it down. It had no bones, possibly no shell. Its re-
mains may never be found; its soft body may have left no
remains.
Beyond vertebrates, the skein is tangled. Nature tried
many types of bodies before she found one fit for a fish.
That was no mean honor. Fishes are highly organized ; they
stand high in the tree of life. The parts they transmitted to
posterity made frogs, lizards, eagles, monkeys, and man
possible. No essential part has been acquired since the first
fish laid the keel on which every vertebrate builds its body.
The very bones of our middle ear began their career in the
arch of the gill of a fish. The wonderful mechanism by
which we know when we are right side up was invented by
a fish.
What makes a body fit for a fish? What did an invertebrate
have to have before it could think of becoming a shark or a
sturgeon or a cod?
No protozoon would do; it has only one cell. The lowest
multi-cellular animals are sponges; but they are primitive
and lead a plant's life. Next come jellyfish, polyps, corals.
Some drift with the current, others settle down to build
coral reefs from their limestone skeletons. They have in-
sides for circulation and digestion, but their body is built
on the plan of a tub.
The next three higher groups, flatworms, threadworms,
wheelworms, look like something; the first two especially.
With them nature tried out an epoch-making experiment —
bilateral symmetry: two sides, two ends. They could tell
right from left and knew whether they were going ahead
or astern. Good-by to the old watchful waiting, or drifting-
round-the-circle days. Strenuous life moves straight ahead.
Earthworms seem low to us. But a jellyfish would have
to look up to them, they are so highly organized; even an
75
WHY WE BEHAVE LIKE HUMAN BEINGS
amphioxus respects them. They have regular parts; they
repair lost parts better than a surgeon. They have a sug-
gestion of a backbone and spinal cord; mouth, esophagus,
intestine with posterior opening; nervous system, brain and
nerve chain; pulsating vessels to circulate the blood; kidneys;
striated muscle. If our vertebrate ancestor was no worm, it
was a worm-like form. The fishworm has the form and all
the essential parts. It even has two sexes in one body; it is
a true hermaphrodite.
With molluscs nature experimented with soft bodies pro-
tected by shell armor. It was a pretty idea, and gave us
pearls, clams, oysters, and snails; but the shells so slowed
them up and weighed them down they could never get away to
a fast start or far from the mud.
Starfish represent another experiment. Possibly our deci-
mal system is due to the two five-fingered hands inherited
from a starfish ancestor.
Joint-foot arthropods are high invertebrates. Some have
very perfect bodies and enough instincts to fill a book. They
are segmented and have well-developed legs — though neither
grasshopper, cricket, nor locust goes "on all-four," as Leviti-
cus misinforms us. They go on all six; spiders and scor-
pions, on all eight.
That exhausts the possibilities. But which invertebrate
line is founder of vertebrates is not yet determined. It may
have been a fishworm. It may have been a scorpion, or a
horseshoe crab. It may have been an unknown family which
split, one branch leading to the amphioxus, which has a real
notochord, but no skull and no red blood.
Poor fish as it is, the amphioxus is the nearest living ances-
tor of vertebrates. They live a quiet life near the shore,
generally buried in sand up to their gills. They have the
makings of a true fish, even to the nervous system; but are
only a fish in the making. And of all the bodies nature tried
out during countless millions of years, no survival has the
76
THE EVOLUTION OF THE EARTH, LIFE, AND SEX
long, slender, segmented body that so closely resembles the
amphioxus as a fishworm,
6
Subkingdom I, Protozoa; subkingdom II, Metazoa. That
is all. Man belongs to the second subkingdom: his is a
many-celled body, all from an original cell.
Flower in crannied wall may be more poetic, but if we
knew all about the one-celled ameba, we should know more
about life than we are likely to know for some time. If we
knew why several Protozoa decided to found a co-operative
society and so the subkingdom Metazoa, and if we had the
minutes of their first meeting, we should be able to manu-
facture animals to suit our fancy. If we knew the nature
of the jelly called protoplasm of the ameba's body, we should
know what life itself is.
With the mere mention of the word "protoplasm" we have,
as the farmers say, a lot of hay down. We cannot get all
our "hay" in before it rains; some of it spoils. We call in
the biochemist, but by the time he gets it in a test tube or
stains it so that he can see it, what was living jelly is dead.
He examines only the remains — the "debris," as Lull calls it.
Protoplasm (first-molded-thing) is called living jelly be-
cause it is about of the consistency of jelly. It is semi-fluid,
generally transparent, and colorless. It may contain granules
which make it grayish in color and semi-transparent. Some
of these granules may be stained, and are called chromatin.
This appears as a central spherical mass, and is called the
nucleus {nux, nut) ; the remainder of the protoplasm is called
cytoplasm.
Protoplasm is known only by the body it keeps; but
whether one cell is the entire body or only one in a body of
billions of cells, every cell has certain properties or func-
tions. It is self-supporting; it has its own definite wall,
or is so cohesive that its outer surface serves the purpose of a
77
WHY WE BEHAVE LIKE HUMAN BEINGS
wall. It eats ; it must have food or it dies. It must get rid of
waste. It moves. Its movements may be of the flowing kind
or "ameboid" — part or parts of it flow out in processes, like
the movements of the ameba. Or, it may be covered in whole
or part with fine cilia which set up whipping movements.
It is excitable or irritable: when touched, it moves. It re-
sponds to certain stimuli. It has conductivity: a stimulus at
one side may lead to movement on the opposite side. It can
co-ordinate its movements, as it does in such harmonious
actions of the cilia or the pseudopoda in ameboid move-
ments. It grows or has the power of reproduction.
The ameba can be studied only under the microscope. It
is literally a speck of living jelly, but it is as "alive" as an
elephant or a whale. It goes about for food. It flees from
danger. It is sensitive to stimuli from without. It breathes
oxygen and gives off carbon dioxide; collects, digests, and
distributes food; excretes waste; reproduces its kind. It can
learn from experience. It is organized for one purpose only:
life. Within that limit it fails in no essential.
What is the ameba? Life. What is life? Protoplasm —
ultramicroscopic, unanalyzable ; but only living if it behaves
like a living being.
Protoplasm is 72 per cent oxygen, 13.5 per cent carbon,
9.1 per cent hydrogen, and 2.5 per cent nitrogen. The re-
maining 3 per cent consists of sulphur, phosphorus, chlorine,
sodium, potassium, calcium, magnesium, iron, and silicon.
Add a pinch of fluorine, iodine, and manganese; and that is
what little girls are made of.
Such is the stuff" of life. How about the staff" of life? For,
as Huxley said, while a solution of smelling salts in water,
with a tiny pinch of some other saline matter, contains all
the elements which make up protoplasm, a hogshead of that
fluid would not keep a hungry man from starving, nor save
any animal from like fate. It is equally true that if animals
lived only on dead animals, the animal world would perish
78
THE EVOLUTION OF THE EARTH, LIFE, AND SEX
through cannibalism. Even nature cannot pull herself up
by her bootstraps.
Which takes us out into the open and face to face with life
itself. No one quite knows what life is, but there are certain
fairly accurate tests for life. One is growth. Are certain
bacteria alive? Put them in a suitable medium: if they grow,
they are alive; if not, they are dead. We stop growing
larger, but when there is no growth anywhere in our body
we are dead and our own digestive juices will begin to digest
our body.
The point is that plants are older than animals and bacteria
older than both; and that there is no sharp line between lowest
animals and lowest plants or any general agreement as to
whether bacteria are plants or animals. Nor does it make any
particular difference to us. What matters is that animals
must rely on plants or other animals for their growth-material
and that plants are not so dependent; they can live on mate-
rials which would be death to animals. With carbon dioxide,
water, and nitrogenous salts, a plant will multiply a billion-
fold — "building up the matter of life from the common
matter of the universe." But where do they get their nitro-
genous salts?
Bacteria. Their daily bread is a few simple minerals.
Without bacteria, air, land, and ocean to-day would be life-
less. They were the primordial chemists, finding food in a
foodless world, drawing their energy and their nutrition
direct from lifeless compounds. We shall have a closer look
at them later. It is enough now to pay a tribute to them
for having helped form the crust of the earth and so prepare
the land and sea for the evolution of higher life. Without
them, life on earth as we know it is inconceivable, nor would
life be possible to-day without them.
In other words, this earth was once lifeless and about as
big as Mars, half its present size. To imagine it as it was
then, Osborn asks us to subtract all mineral deposits of
organic origin, such as organic carbonates, phosphates, and
79
WHY WE BEHAVE LIKE HUMAN BEINGS
lime; carbonaceous shales and limestones; graphites; silicates
derived from diatoms; iron deposits; humus of the soil; soil
derived from rocks broken down by bacteria; and ooze of the
ocean floor. The shells of microscopically small diatoms
alone make up 6 per cent of the bottom of ten million square
miles of sea!
These organic deposits cover the earth miles deep. They
fitted it for higher forms of life. And all due to microorgan-
isms. Geikie thinks it might have required four hundred
million years.
7
The earth itself, according to Chamberlin, our foremost
geologist, is an offspring of the sun; as are the other seven
planets, the twenty-six satellites, and the eight hundred planet-
oids which make up our planetary system. In giving birth
to them, the sun parted with less than an eight-hundredth part
of its body, the earth itself representing about three-thou-
sandths of 1 per cent of the sun's substance. In other words,
our earthly home is considerably less than the proverbial drop
in the bucket of our heavenly parent.
Birth of earth and other planets was due to a passing star.
It was bigger and denser than the sun and consequently had
a greater pull. It attracted little bits of the sun away. One
bit is our earth, held to its course by pull, by gravity. Were
the pull of the sun to be altered, the orbit our earth makes
about the sun would change.
It happened this way. The sun is so hot that it explodes
sun-stuff or gas-bolts. They travel 300 miles a second and
may project 300,000 miles beyond the sun's surface before
they drop back again.
Along came a huge star, itself a sun, bigger, denser, than
our little sun. Its pull was so great that the sun stuff that
happened to be erupting was drawn so far out it could not
fall back. It was mostly gas, the parts nearest the sun hottest.
80
THE EVOLUTION OF THE EARTH, LIFE, AND SEX
It kept on moving, condensing; it came finally to be broken
up into bits. Each bit kept on traveling in its own orbit about
the sun — ^held by the sun's pull, but each too distant to be
pulled back into the sun.
Chamberlin assumes that several gas-bolts were pulled
from the sun. From the first grew Neptune and Uranus;
from the second, Saturn and Jupiter. These great planets
are still hot and gaseous. On the return journey the pass-
ing star loosed another gas-bolt; from it grew the terrestrial
planets: Earth, Venus, Mars, and Mercury.
The earth to-day is five and one-half times heavier than
an equal volume of water. At first it y/as not so dense,
more nebulous, and of varying density. Knots of denser
matter condensed into liquid or solid cores. These grew by
drawing into themselves smaller knots. This could happen
because their orbits kept changing according to their change
in density. The largest core kept on picking up bits that
came in its path. It kept on growing denser. The earth is
still growing.
When only a nebulous knot, the earth was magnetic, and
is now. It "selected" the matter that was to form its core:
iron, nickel, cobalt. It picked up planetesimal dust, meteor-
ites, etc. It began to draw an atmosphere about it. From
the atmosphere fell the rain, the primitive waters in the earth's
cavities. Thus there came to be a lithosphere, a hydrosphere,
an atmosphere.
Our atmosphere is chiefly nitrogen, oxygen, hydrogen, and
water-vapor; all were in the original nebulous knot. Some
gases were carried into the inside of the earth, to be let
loose again by volcanic action. Some simply gathered more
and more closely about the earth; the earth's pull was enough
to hold them.
When the young earth had reached 30 per cent of its
growth, it could begin to draw to it the water-vapor that had
been shot from the sun. Thereafter, the water on the earth
and in the atmosphere strove to maintain an equilibrium. But
81
WHY WE BEHAVE LIKE HUMAN BEINGS
the temperature kept changing and the atmosphere kept cir-
culating. The earth has always had its arid as well as its
humid areas; it was never enveloped in a "warm moist atmos-
phere."
Our earth began, then, with a small lithosphere, a small
hydrosphere, a small atmosphere. These reacted on each
other, always in co-operation, always in competition and an-
tagonism. Even to-day land, water, and air struggle for the
mastery. The story of that struggle is the history of the
earth. The oldest rock record known shows that the earth
was then about as it is to-day, mostly land areas, wide seas.
Water and air struggle to wear the land down, only to have
it buckle up again in some new mountain range, the waters to
retire to new abysmal depths.
As long as volcanoes last, the earth will not get over-
heated because of pressure toward the core. Through vol-
canoes, as through the pores of our skin, the earth rids itself
of excess heat and fluids. Thus, the earth is always becoming
more solid, more rigid ; its lighter and more mobile material
is constantly being forced to the surface, again to be buried,
reheated, reorganized, and part of it to be belched forth
again. Its core now is chiefly metallic, its envelope of a
fluid-like nature; the whole, immobile, refractory, crystalline.
The gas-bolt that was pulled by a passing star from its
parent sun and grew into earth carried the elements of life.
When the earth was fit for life, life came; the inorganic
elements reorganized into organic compounds. That was as
radical a move in the earth's evolution as was its break from
the sun.
8
With the words we build with our A B C's we name the
universe nature builds with her L M N's — as the Romans
called them, from the letters on the tablets on which children
learned to write. The world of matter is what it is because
82
THE EVOLUTION OF THE EARTH, LIFE, AND SEX
the elements are what they are and what they become when
chemically united. Each element is unique and has unique
behavior, but matter assumes an infinite variety of forms
because two or more elements can surrender their individ-
uality and become a new substance with unique behavior.
A-r-w is a meaningless mixture of letters ; w-a-r is a loaded
word and has infinite possibilities. With only two elements,
thousands of new substances are possible; with three, the
possible combinations are enormously increased. With C, H,
0, and N, and a pinch of salts, every living thing is possible.
Why? It is their nature.
"Nature" can mean anything. For example, sodium is a
metal, lighter than water; a drop of it on our tongue or on a
sweaty hand catches fire and burns a hole. Chlorine is a
gas, heavier than air, so corrosive that a few whiff's are fatal;
it was the poison gas in the World War. Of these two ele-
ments combined in one, we use about thirty million tons a
year. It is found on every table, eaten at every meal.
Sodium chloride is common everyday table salt: in large
quantities, fatal; in moderate amounts, good for man and
beast.
What is the nature of salt? Why do we require a certain
amount of salt in our diet? Why will salt preserve meat?
Why do sodium and chlorine lose their specific characters
when united as salt? Why is sodium electrically positive,
chlorine negative? Why is the human body rubbed with
wool positively charged; rubbed with silk, negatively
charged? What is the nature of electricity?
The nature of things is what we know of things. Of some
we have the number, we know their law. For example, with
hydrogen, chlorine forms hydrochloric (muriatic) acid, so
strongly caustic that it will eat the enamel off a tooth or
dissolve a bone. Dogs' stomachs secrete more hydrochloric
acid than ours; they digest bones better than we do. Why
our stomach secretes hydrochloric acid is one question; how
our body separates the chlorine out of salt and the hydrogen
83
WHY WE BEHAVE LIKE HUMAN BEINGS
from water (both difficult chemical processes) and com-
bines them into a powerful acid that will digest gristle, is
another. The first question is on a par with thousands of
others as yet beyond the pale of science.
What is the nature of elements? The answer is so astound-
ing that the world has hardly yet recovered its breath, so
far-reaching in its implications that science has not yet
grasped its full significance.
Science recognizes eighty-two and actually knows seventy-
nine stable elements. There are, in addition, ten heavy
radioactive elements, which, unlike the stable elements, are
transmuting themselves into lighter elements.
The unit or smallest quantity of an element which takes
part in a chemical reaction is an atom (uncutable).
Recently, the atom has been "cut." It consists of unit
charges of positive and negative electricity called electrons.
While electrons are alike in strength of electric charge, nega-
tive electrons have a mass or inertia l/1845th of the lightest
known atom, hydrogen. In other words, the weight of the
negative as compared with the positive electron is almost
negligible.
An atom, then, says Millikan, consists of a heavy core or
nucleus of free positive electrons about which are grouped
enough negative electrons to render the whole atom stable
or neutral. "Hence the number of negative electrons out-
side the nucleus must be such as to have a total charge equal
to the free positive charge of the nucleus; otherwise the
atom could not be neutral." As the weight of the atom
depends almost entirely upon its nucleus, and as hydrogen is
the lightest element, the atomic weight of other elements is
an expression of their weight compared with that of
hydrogen.
The atomic number of hydrogen is 1. Its nucleus carries
one electron of positive charge; outside that nucleus is one
electron of negative charge. The two electrons thus neu-
tralize each other; the result is a system, an atom of
84
THE EVOLUTION OF THE EARTH, LIFE, AND SEX
hydrogen. The heaviest known element is uranium; its
atomic weight is 238. Its nucleus, therefore, must contain
238 positive electrons. But as its atomic number is 92, its
nucleus must carry, in addition, 146 negative electrons to
neutralize the 146 positive electrons over and above the 92
positive electrons free to neutralize the 92 negative electrons
outside the nucleus. The result is a system, an atom of
uranium. Remove one free positive electron from the
nucleus of that atom; it is no longer an atom of uranium.
Remove 10 free positive electrons; it is an atom of lead.
Remove 13; it is an atom of gold. Remove 91; it is an
atom of hydrogen gas. The 92 elements are determined,
says Millikan, simply by the difference between the number
of positives and negatives packed into the nucleus. All
elements, ideally at least, are transmutable into one another
by a simple change in this difference.
Magnify the nucleus of an atom one billion times; it is
still too small to be seen in a microscope. Multiply that
nucleus ten billion times: the outer electrons are now three
feet from the nucleus, but the nucleus itself is not yet as big
as a pin-point. The nucleus, then, is less than 1/10,000
the diameter of the atom — and yet it may contain, as does
the uranium atom, 384 electrons. No wonder that Millikan
can shoot helium atoms by the billion through a thin glass
evacuated tube "without leaving any holes behind." Atoms
themselves are mostly "holes," as is most of our solar system.
The negative electron compared with the size of the atom
itself is no larger than is the earth compared with the radius
of its orbit about the sun. And yet atoms themselves are
"infmitely small" ! Electrons must be infinitely smaller. Or
rather, smallest conceivable — for the electron itself is now
believed to be the indivisible, ultimate unit of matter.
When matter in the form of an electron moves, there is an
electric current. Which means, says Millikan, that electricity
and matter look like different aspects of one and the same
85
WHY WE BEHAVE LIKE HUMAN BEINGS
thing. There is proof that electricity is material; there is
evidence, but not yet proof, that all matter is electrical.
The electron itself, then, is a speck of electricity; it has
definite granular structure; it is the primordial stuff of the
universe of matter. When specks of electricity are combined
in certain ways and proportions, certain neutral systems
result, and we have the atoms of the elements of all physical
bodies which are described in terms of chemistry and
physics — matter and energy.
Science knows nothing of the ultimate origin of matter
or of the source of energy; it only accepts both as facts and
goes on with its business of trying to find out what matter
is and what energy can do. In other words, the problem of
the origin of life is locked up in the origin of matter and
in the nature of energy. But the line between life and death
is not unlike that between organic and inorganic, a vague
shadowy line crossed from day to day in the chemical labora-
tory. Life has been produced in no man-made shop; proto-
plasm, the chemical matter of life, has been. It does every-
thing but live! It does not seem fit for life.
9
Life cannot live without food. Food cannot be had in a
red-hot sun, in the interior of the earth, or in a nebula of gas.
We hear much of "fitness," but always the fitness of the
organism. There is another fitness — that of the earth itself.
Before trees, there was no arboreal life; before plants, no
animals. Only as the fitness of the environment evolved
could life evolve. Environment and life go together. Fit-
ness of environment is as essential to life as it is to a snow-
flake, a salt crystal, a diamond, or a river; nor are these
more thinkable out of their environment than is any living
being, or more easily "explained" away. The fitness of ihe
earth's environment for life has been beautifully worked out
by Henderson.
86
THE EVOLUTION OF THE EARTH, LIFE, AND SEX
The earth keeps its atmosphere because of its size and
relation to the sun. This fact and the nature of its atmosphere
led to winds and clouds, rain, snow and ice, lakes and rivers,
oceans and ocean currents, tides, and magnetic and electric
phenomena.
In the earth's atmosphere were carbon, hydrogen, and
oxygen. From carbon and oxygen came carbon dioxide;
from hydrogen and oxygen, water. With water, carbon
dioxide, and carbon compounds, living things became pos-
sible. These three. The greatest of these is water.
There is nothing like water. Over seventy per cent of our
body weight is water. Much of life lives in water and all
of life dries up without water. No water, no life. Life as
we know it is inconceivable without water. In fact, Prout,
the theologian, thought it the most remarkable instance of
"design" in all nature: "Something done expressly, and
almost (could we conceive such a thing of the Deity) at
second thought, to accomplish a particular object."
Why does the highly inflammable gas hydrogen, united in
certain proportions to oxygen, another gas and necessary for
combustion, always produce water, which is not only not
inflammable, but a hindrance to combustion? The "why"
of water is unknown. Much is known of its behavior, in
some respects more weird than that of a child. We speak
of "solving" problems. Water is the great solvent. We may
not suff'er from water on the brain, but conscious brains are
85 per cent water. Were our brains only 60 per cent water,
they would be as dense as tendons; if only 20 per cent, as
hard as the skull itself; and if 10 per cent, just fat.
More substances will dissolve in water than in any other
liquid. Each year the earth's rivers carry to the sea five
billion tons of dissolved minerals and other unnumbered
millions of tons of carbon compounds. Water is the great
dissolvent of food before it is taken into the cells and as it
leaves the body through the sweat glands, kidneys, or lungs.
Over 90 per cent of the blood of our transport system is
87
WHY WE BEHAVE LIKE HUMAN UEINGS
water, holding in solution iodine, bromine, iron, sulphates,
urea, ammonia, etc. The water excretion of our body carries
off in solution countless organic substances, as well as
chlorides, bromides, iodides, phosphates, potassium, sodium,
ammonia, magnesium, iron, carbon dioxide, nitrogen, argon,
etc.
Chemical reactions take place in water; electrical forces
are at work, forces which bind atoms into molecules and
cause chemical reactions. Acids and salts are electrolytes:
they can carry electric currents, they can be dissolved by
electric currents. In dissolution, ions (goings) are formed;
they carry the current.
Life is dynamic. Every living thing is a dynamo. Its
electricity, like that of batteries, comes from the ions of
atoms of electric charge set free when molecules of acids,
bases, and salts are split up. Ions are back of protoplasm
and essential to all life processes. Water is the supreme
solvent for ionization.
A heart cut from a living body keeps right on beating
provided it is kept in proper solution. What is "proper"
for a heart? A change in the hydrogen ion concentration
of one ten-billionth part in that solution is improper: the
heart stops. The control over such salt solutions is now so
perfect that glands can be kept alive while awaiting trans-
plantation into foreign bodies.
Water is chemically and physically stable; inert in the
atmosphere; almost inactive on the surface and in the soil.
It changes few substances, it is not easily changed. It is
almost everyv/here present in the soil ; and in the atmosphere
as clouds and vapor. Its high specific heat tempers both
summer and winter. The tropics is a vast warm reservoir;
the poles, cold reservoirs. This m.akes for circulation of the
atmosphere and ocean currents. Water's high specific heat
also makes it possible for man to produce 2,400 calories
a day, enough to raise his temperature to 150 degrees, and
yet keep his body at its normal temperature.
THE EVOLUTION OF THE EARTH, LIFE, AND SEX
Water can be cooled to the freezing point; it can get no
colder than ice. With the thermometer forty degrees below
zero, a cake of ice is almost the next best thing to a stove.
Lakes and oceans cannot get colder than the freezing point
of water. This makes water a powerful regulator of the
earth's temperature.
Most substances contract with cold. If water obeyed this
law, most of life would go out of business every winter.
Water loses density on cooling; it rises to the top. Lakes
and rivers freeze from the top down, not from the bottom up.
Life is colloidal, like glue, jelly, protoplasm; it has no
definite, rigid, predetermined form, as has a crystal. Colloid
structures are complex beyond man's present capacity to
resolve them when in the form of protoplasm. Protoplasm
can live because it can absorb food substances. The force
which operates upon colloidal structure is surface tension of
water. Surface tension is at the root of all food metabolism.
In short, water is a vital part of the evolutionary process
which fitted the earth to be the home of the life that culmi-
nates in man; fit of its very nature, as Henderson says,
"with a fitness no less marvelous and varied than that fitness
of the organism which has been won in the course of organic
evolution."
Every living thing is but a v/atery solution; man himself,
but a porous sack of water. But water alone could not have
led to life without carbon dioxide. Carbon dioxide is even
more pervasive than water; it is everywhere.
Carbon dioxide (carbonic acid or carbonic acid gas — one
atom of carbon, two of oxygen) is colorless, has an acid
taste, a pungent smell. Inhaled by animals, death follows
from asphyxiation. Eaten by animals, in the sugars and
starches of plants, it "burns"; what is left over is carbon
dioxide. Were it not a gas, the task of ridding the body
of it would be impossible; were it not a freely soluble gas,
that task again would be impossible.
Only carbon dioxide enters water as freely as it escapes
89
WHY WE BEHAVE LIKE HUMAN BEINGS
from water. As water is made up of hydrogen and oxygen
so firmly wedded that only unusual force tears them apart,
so water and carbon dioxide are inseparable companions:
in water itself, in fire, in air, in the earth. Only its unique
mobility and its wide distribution have made plant life
possible.
The lilies of the field toil not; the sun does it for them,
using carbon dioxide of the air and of the water. The
cattle of the field have to go to the lilies: the lilies will not
come to them. Cattle toil with the sun's energy of green
grass. We too are children of the sun and toil with its
energy stored in food plants. For example, a gram of
glucose contains 3.7 heat units of solar energy. When a
muscle burns that gram, the 3.7 units are spent: the glucose
was a temporary depository of energy. The energy was
released by burning, oxidation.
Glucose is a carbohydrate — C6H12O6. Ninety-five per cent
of our body can be accounted for by these same symbols —
C H 0; for water, we need only hydrogen and oxygen; for
carbon dioxide, only carbon and oxygen.
When heat and energy were liberated from glucose, the
oxygen was torn from the carbon and hydrogen. Oxygen
is almost unique in its energy-liberating processes. Com-
pounds of carbon, and especially of hydrogen, yield great
heat in oxidation. No source of energy so good as oxygen.
No transformers of energy so great as hydrogen and carbon.
Together, these three elements have unique "fitness for the
organic mechanism. They alone are best fitted to form it
and set it in motion; and their stable compounds, water and
carbon dioxide, which make up the changeless environment,
protect and renew it, forever drawing fresh energy from the
sunshine."
Water is not an organism; it is not life; it is inorganic.
Carbon dioxide is not an organism; it is not life; but it is
organic. The carbon makes the vital diff"erence. Protoplasm
is a very wonderful substance. Remove its carbon: it is
90
THE EVOLUTION OF THE EARTH, LIFE, AND SEX
no longer protoplasm ; it is not even an "organic" compound.
The chemist does not "wonder" about protoplasm; he finds
carbon wonderful enough.
What is carbon? The lead in the pencil with which I
write, for one thing. Charcoal is carbon. So is lampblack.
Also diamonds. What is an element? A system. Each atom
of each element is a system. Carbon must be thought of as
having form, shape, size, mass, architecture. Build atoms
of carbon one way, and you have a molecule of diamond;
another way, and you have a molecule of lampblack. Carbon
alone among the elements can form the skeleton of the com-
pounds known to organic chemistry. It is a unique sub-
stance; in its way, as unique as life itself. It is unique
in its capacity to enter into relationships with other elements.
One atom of carbon can unite with from one to four other
atoms to form a compound. Carbon atoms can form ring
compounds, the rings themselves may unite with carbon
chains, and so on in bewildering possibilities. With only
fourteen atoms of carbon and thirty of hydrogen, it is possi-
ble to form 1,855 distinct and stable compounds. The
difference between acetylene and paraffin is in the way their
carbon and hydrogen atoms are combined.
Add oxygen to carbon and hydrogen: the number of
organic compounds possible is at once multiplied enormously.
Alcohol, glycerine, lactic acid, ether, carbolic acid, sugar,
cotton, camphor, olive oil, starch, oil of wintergreen, vanilla,
and the venom of the cobra. What a mess — solids, liquids,
gases! Yet only three elements enter into their make-up:
carbon, hydrogen, oxygen. The list only suggests the
diversity that follows from a few of the thousands of possible
combinations of three seemingly simple chemical elements.
About a half-million organic compounds are already
known to chemists. Back of all, carbon. Hydrogen and
oxygen, next in importance. These three made life possible:
as water, the carrier of life ; as carbon dioxide, the substance
on which life hangs.
91
WHY WE BEHAVE LIKE HUMAN BEINGS
From such simple carbon compounds as the baby earth
inherited from parent sun, grew the more complex and
subtle carbon compounds that to-day peer into microscopes
at dividing cells and shake test tubes over gas jets to discover
what life is.
The earth's physical conditions were always changing.
Matter itself kept changing. Earth, energy, matter, are
bound together in one continuous change: the history of
that change is the story of evolution. In the process of
change life itself was evolved. But only after the environ-
ment into which life fits itself had evolved to the point that
it was fit for life. Fitness of life and fitness for life are
two views of the same tale; and both incidents in the greater
story which goes back through the young earth to the old
sun, and thence out into the wide universe. Forward, to
eternity.
10
Snowflake, salt crystal, diamond, are described in terms of
matter and energy; explained in no terms known to science.
Life also is described in terms of matter and energy. The
form or substance of life is complex, much more complex
than snowflake, salt crystal, or diamond.
This complexity of living beings requires a mechanism
organized for durability. The lowest plant is a more com-
plex mechanism than is a raindrop, a snowflake, or a crystal.
But, like them, living beings are subject to gravity, and if
they break the laws of physics and chemistry they no longer
live: what was complex and had a certain behavior is now
less complex and has a different behavior.
Living things escape the fate of less complex compounds
by holding their fate in their own hands to an extent denied
inorganic things. Snowflake and bacterium "die" under a
sun's ray; an alga synthesizes protoplasm; a lizard crawls
into the shade; a man hoists an umbrella. But one action
is no more "explicable" than the other.
92
THE EVOLUTION OF THE EARTH, LIFE, AND SEX
The lizard's energy is of a different type from that of the
bacterium; it has a wider range, it can better adapt itself
to its environment. But otherwise its vital processes, though
of a higher order, must be of the same kind.
Life, in any and all forms, to go on as life, must exchange
matter and energy with its environment; it takes in food,
excretes waste.
The smallest known molecule — hydrogen — weighs a three-
million-million-million-millionth of a gram. It travels a mile
a second. Do chemistry and physics "resolve" it? An
electron is smaller and travels faster. Is it less mysterious
than a seed of mignonette? Why does a molecule of hydro-
gen have only one kind of behavior, a molecule of oxygen
two kinds, a molecule of carbon four kinds? Heredity?
Why does one speck of protoplasm grow into mignonette,
another into man? Heredity again. But always: matter,
energy. The matter is differently combined, the energy
comes from different sources.
Thus, plants obtain such matter as carbon dioxide, water,
and mineral salts, from the air and soil. With the aid of
energy (sunlight) they transform these into such other
matter as sugar and oxygen. The oxygen returns to air
and renews it. What becomes of the solar energy? Animals
eat the sugar; within their body it is burned, setting free as
muscular force and heat the energy the plant got from the
sun. What becomes of the by-products? Eliminated by
the animal as carbon dioxide and water: food fit for plants.
The food goes round and round.
Living matter does not produce something out of nothing,
neither the matter of its own body nor the energy expended
in building its body or in keeping it alive. Plants conserve
energy, animals dissipate it.
Nothing is destroyed, nothing lost. Wliat is here has
always been here, or gathered up from the dust of the
universe. Energy from the sun changes matter, alters it,
evolves it. Matter itself is indestructible; the energy itself
93
WHY WE BEHAVE LIKE HUMAN BEINGS
is transformed, flows in but one direction. There is enough
in the sun to keep earth and life going for untold millions
of years.
Untold millions of years ago, the sun's rays were impelling
forces as they are to-day. Under their influence, the facile
carbon took on new and more complex forms as it built into
its structure hydrogen, oxygen, nitrogen, sulphur, phosphorus,
chlorine, sodium, potassium, calcium, magnesium, and iron.
This took time. But the times were ripe when water began
to collect in pools, and there were shores. Circulation, at
any rate, went on then. Evaporation made for clouds : water
came from above; capillary attraction brought the waters
up from below. Wet and dry seasons alternated. The
elements favored concentrations and resolutions. All favor-
able to colloidal growth, to fluent forms, and to pliancy.
The development of colloids must have been as important
in the building of life as were the organic compounds. Even
early in the earth's growth the organic compounds must
have tended toward colloid rather than crystalline direction.
Within limits, the colloid was more stable. Crystalloids were
subject to dissolution; in solution, they contribute to the
upbuilding of colloid capsules.
Conceive of several units or globules of colloidal proto-
plasm wrapped up in an envelope, and we have a bacterium.
Add more protoplasm, rearrange the internal mechanism, and
we have a plant cell. Increase the complexity of the internal
mechanism, add more colloid globules, and we have an
ameba. Give it a definite outer garment, and we have such
cells as we are made of.
A true cell diff'ers from a bacterium in its greater com-
plexity of structure and more stable dynamic process ; it lives
faster because it is better organized to take in what it needs
and get rid of the husks. The animal cell has greater flexi-
bility than the plant cell; it can travel as well as grow.
It can live faster, spend more, and sleep less. Both diff"er
94
THE EVOLUTION OF THE EARTH, LIFE, AND SEX
from a crystal in having a larger number of substances for
chemical activities to organize.
While the shape of living beings and crystals, says Loeb,
is primarily determined by the chemical nature of their
material, their mechanism of growth is different. Crystals
grow, and even restore their old form when mutilated; but
only in "supersaturated undercooled solutions of the mole-
cules of which they are composed. Living cells grow in
solutions of low concentrations of simpler compounds tlian
those of which their cells are composed." They grow because
they synthesize large insoluble molecules from comparatively
small soluble molecules. The crystal cannot organize in
colloid form ; it has no such substratum for dynamic changes.
The nature of the earliest form of life we may never
know. Of living organisms, bacteria are presumably the
lowest, simplest, and most primitive. Sulphur bacteria obtain
their energy by the oxidation of sulphuretted hydrogen to
sulphuric acid; with that energy they fix nitrogen of the
air and synthesize carbon compounds. We may speak of
their energy as a bioelectric current; their growth, as electro-
synthesis. They deal direct with inorganic matter. They are
a link in organic evolution. Whatever life is, they had it.
They made more complex bodies possible: lowest plants.
The microscopic one-celled algae, through their green
chlorophyl, began to store energy from sunlight. For this
they needed only a cell membrane; inside which they fell
"asleep in immobility."
The next step was the lowest animal, an organism so
complex that it got its energy from plants. It was a new
kind of power plant. But it had to go after the energy it
put to work; the plant comes to the animal only as borne by
the wind or water.
Animal and plant evolution forked — one went one way,
the other another. But animals had to know which way
the plants went.
The first lesson animals had to learn was, "Keep moving."
95
WHY WE BEHAVE LIKE HUMAN BEINGS
The key to their evolution is their specialized ways to find
food and go to it, and to know and to avoid their enemies.
Plants, on the other hand, were enjoined to keep their place
in the sun. The green leaf is the key to their evolution;
their interest in locomotion is chiefly confined to their seeds:
these must meet their mates and be carried to suitable soil.
The primitive animal cell had the world before it and
could go where it liked, always provided it never ceased to
function. It had to keep in touch with a commissary depart-
ment. Life, as well as armies, travels on its belly.
Some dug in, as the Sporozoa; some went in for speed, as
the lively Infusoria ; some just dragged around, as the ameba
does. And these three types of primitive organisms are
represented to-day by the encysted, ciliated, and ameboid
cells of our body.
Where the single-cell animals began to combine and pool
their interests, the tree of life took on new capacities for
growth. The sky was the limit — and the bee beat the lark
to it.
Both bee and lark are animated and have vital energy.
And that is all there is to Animism and Vitalism.
An ameba engulfs a diatom and casts out the shell. A
drop of chloroform suspended in water engulfs a shellac-
coated spicule of glass and casts out the spicule. Known
laws of physics and chemistry suffice to describe both actions.
But neither action can yet be fully described because not
all is known of the energies involved in the two actions.
More is known about the mechanism in which energy is
manifested in the drop of chloroform than in the blob of
protoplasm. It is known that the ameba is activated by
forces from without, as is the drop of chloroform; not much
is yet known of the mechanism of the ameba by which it
makes its response. The energies which move it are vital
only because complex mechanisms, such as amebae and otlier
living protoplasm, possess what is known as vitality, life.
The rays which blister paint and my skin, dry up amebae,
96
THE EVOLUTION OF THE EARTH, LIFE, AND SEX
and impel green leaves to synthesize carbon compounds, come
from the same sun. These rays are forms of energy: they
do things. They animate nature. When we stop eating that
stored energy, we lose our stored vitality and soon become
inanimate.
The chemist can synthesize many organic molecules; he
cannot yet synthesize a living protein molecule — he does not
know its exact composition and architecture. If he could
synthesize a living protein molecule, he could probably
synthesize protoplasm and build a living cell. If he could
build a living cell, there is no telling what he might not do,
for, as Millikan says, when nature's inner workings are once
laid bare, man finds a way to put his brains inside the
machine and drive it whither he will.
In other words, we shall know how life evolved when we
can evolve life. That day will probably come; it is yet a
long way off.
Facts of evolution, yes; by the million. Museums,
libraries, and laboratories full of facts. But no one law
yet propounded begins to fit all the facts. Two hypotheses
have become famous and have passed into current literature ;
they have given rise to world-wide controversy. They did
not describe evolution ; they did serve mightily to open men's
minds to new views of life and wider conceptions of nature.
Lamarck and Darwin will remain great names in the history
of the science to which they gave their lives, but which was
to develop into a real science of life only within the last
few decades.
11
A fundamental criterion of life is growth. The outstand-
ing phenomena of life are universality and prodigality. The
only line life knows is the food line. Nature seems to
abhor a lifeless vacuum. Life abounds in deep seas, in hot
springs, in ice-cold caves, on the eternal ice of glaciers.
There are fish that climb trees, spiders that live under water.
97
WHY WE BEHAVE LIKE HUMAN BEINGS
In a three-by-four-inch garden patch Darwin found twenty
kinds of flowering plants. There are seven thousand million
diatoms in a square yard of pond water. One Alpine glacier
supports fifty million wingless insects of a single species.
In one bucket of water there may be five million phos-
phorescent microorganisms. A ship may plow through count-
less millions of billions of them for hours. In a pinch of
soil there may be twenty billion colloidal food particles
supporting a hundred million bacteria, fourteen million fungi
and algae, and five thousand protozoa.
Life is a spendthrift breeder. Elephants are the slowest,
yet Darwin calculated that one pair in 750 years would
have 19,000,000 descendants. Australia has often told the
world what one pair of rabbits can do. Fish are worse.
A cod can lay 6,000,000 eggs; a ling, 28,000,000. Even
the ling would be crowded out of the sea if just one oyster
were let alone by all and sundry until it had great-great-
grandchildren. If all survived. Lull says, there would
be just 66,000,000,000,000,000,000,000,000,000,000,000
oysters. Their shells would make a pile eight times the
size of the earth!
Oysters only produce 60,000,000 eggs a year. A starfish
produces over 200,000,000. But even a starfish's progeny
are but a drop in the bucket compared with the yield of
one — not a pair, just one — Paramecium. This animal, just
visible to the naked eye, has been domesticated in a Yale
laboratory by Woodruff. He studied its capacity to occupy
the whole known universe: not our puny solar system, the
universe. At the end of the 9,000th generation there would
not be room for a star or a comet or a nebula in the sky.
The universe would be solid Paramecium.
But the universe is not solid Paramecium, nor have there
ever been 19,000,000 elephants at large at any one time,
nor can we travel from New York to Southampton on a road-
bed of oyster shells. Why not? Because, in short, life is
a fight. Which survive?
98
THE EVOLUTION OF THE EARTH, LIFE, AND SEX
Here is where Darwin got his key to evolution. Nature
herself decides; she selects. Natural Selection.
But, does not like beget like? Are we not all created free
and equal? Darwin knew better; as does every farmer.
Animals breed true; but they vary. Peas in a pod vary.
Rabbits of a litter vary. Identical twins vary. Without
variation, there could be no evolution. Variation is the
law of the universe. Living beings vary, the environment
varies. There is overproduction, and a struggle for existence.
In that struggle the fittest would survive. Harmful variations
would be eliminated, beneficial characters intensified and
modified; characters neither hurtful nor beneficial would
persist through heredity. Man himself carries around two
hundred characters he could dispense with, but which are
not so unfit that nature weeds them out.
There followed much talk of "survival" values and of
"adaptations." One marsupial "survives" because it is a
jumper; another, because it is a sprinter; another, because
it is a climber. One snake survives by turning a tooth into
a hypodermic syringe, his saliva into venom; another keeps
his teeth, but changes his skin to look like that of his poi-
sonous brother; another parts with teeth entirely, and devel-
ops a spine in his gullet to break birds' eggs. He is "adapted"
for climbing.
Remove the "adaptations" from a whale, there is nothing
left. Some whales have big teeth in big jaws and a gullet
big enough for a Jonah. Their equally big cousins have
no teeth and a gullet so small they must strain their food
through a whalebone sieve. They are "right" because the
right kind to yield lots of blubber and whalebone.
Milton's whale, that "at his gills draws in, and at his trunk
spouts out, a sea," would be an "adaptation"! Especially
if its young were born alive and took nourishment from
mammary glands, as all whales do. Whales have no "gills,"
no "trunk." They are perfectly good mammals, as mammal
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WHY WE BEHAVE LIKE HUMAN BEINGS
as bat, giraffe, or man. Why did they go back on their
country and go in for aquatics? Why are some whales as
gentle as turtledoves, others as mean as sharks? Wliy are
there Negritos and Nordics? Natural selection must work
overtime to answer these questions.
What kind of variation may we expect to find in a land-
lubber that takes to water and adapts one branch of its family
to fight sharks and another branch to live on nothing that
would not pass through a finger ring? Did you ever try
to catch food in your mouth and swallow it, fifty feet under
water? Any whale can. The first whale that tried that trick
drowned: it transmitted nothing, not even a taste for salt
water. Think of the "adaptations" a whale had to part
with to become adapted to water.
De Vries, a Dutch botanist, suggested the mutation theory
as a way out. Life does not always vary by slight change,
but sometimes by jumps. Breeders call them "sports."
Perhaps the first tailless ape was a sport. Perhaps man
himself is.
But can the "sport" hand on the essence of its change?
For example, a human sport with four toes can found no
four-toed dynasty unless the four-toedness is a transmissible
trait. Again, the trait which characterizes the sport may
have no "survival" value; it may even prove a handicap in
the struggle for existence. In either case, it will lead to no
permanent change. It is difficult to see how the mutation
theory can work, apart from natural selection.
Some variations are "predetermined": they are inherent
in the developing egg. Or they may be "acquired" after
birth, called out by outside influence. They may be "chance"
variations, subject to no known law; such are the variations
"selected" according to the Darwinian law. Or they may
be "orthogenetic," as Osborn calls them: they seem to point
in some definite direction. Most variations are "continuous"
and of slight quantity: these also enter into the Darwinian
100
THE EVOLUTION OF THE EARTH, LIFE, AND SEX
calculation. Or they may be "discontinuous": of large
quantity, the "mutants" of De Vries. Some books on evolu-
tion abound in such jargon. It gets us no nearer to the
cause of variation.
After the first shock, people began to like Darwin and
his fittest doctrine. "Survival of the Fittest! Aren't we
here? We are the fittest! Darwin says so." Many 0. K.'d
Darwin without knowing that merely to be alive under domes-
tication is no proof of fitness, mental, moral, or physical.
When they realized that they could not count on Darwin for
a Personal Fitness certificate, they lost interest in evolution
and blamed Darwin for having taken them in. And
grounded their blame on the monstrous proposition that
Darwin sought to drive God from the world!
Darwin himself would have been the last soul in the world
to do such a thing. He had no wish to disturb anyone's
religious beliefs. On the contrary, knowing that the pub-
lication of his findings would challenge the Mosaic cos-
mogony, he held back for twenty years and did not publish
until he was actually anticipated by Wallace. And then he
said he felt like a murderer! But no scientist ever less
deserved the reproach of the Church. Nor does it become
the physicist, L. T. More, even in "trying to vindicate the
belief in our spiritual nature," to bear false witness against
Darwin, as he does in his Dogma of Evolution, just issued
by the Princeton University Press. Darwin died as he had
lived, a Christian gentleman.
Darwin did not discover evolution, but he so presented
the facts of and the case for evolution that the world believed.
In the fact that Darwin and Lincoln had a common birthday
(February 12, 1809), Lull sees Darwin as an "emancipator
of human minds from the shackles of slavery to tradition,"
as Lincoln was the "emancipator of human bodies from a
no more real physical bondage." His nobleness of character
and generosity of disposition were not less than Lincoln's.
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WHY WE BEHAVE LIKE HUMAN BEINGS
12
"All that has been acquired or altered in the organization
of individuals during their life is preserved by generation
and transmitted to new individuals which proceed from those
which have undergone change," said Lamarck, a great French
naturalist who died nearly one hundred years ago, blind, in
poverty, a social outcast — for telling the truth as he saw
it! He coined the word "biology"; it thrives. Biologists
have driven a hundred daggers into his theory of evolution
through the Inheritance of Acquired Characters; the theory
is as alive as ever!
To find out if "acquired characters" could be inherited,
thousands of animals were mutilated; Weismann himself cut
off mice's tails for twenty-two generations! They gave it up,
realizing, as Conklin puts it, that wooden legs are not inher-
ited, but wooden heads may be.
I may "acquire" such development of the muscles of my
breast and abdomen that I can dance the "hootchy-kootchy";
that is one thing. To have those muscles cut out is something
else, certainly not an "acquired" trait. The marvel is that
Weismann's silly experiment ever got into print as experi-
mental "evidence" that there is nothing to Lamarck's theory
of evolution.
"Every animal climbs up its own genealogical tree," says
Thomson. But that no more disproves Lamarck's theory
than Weismann's mice that were born with tails. If an
animal never takes the first step, it can never take the second.
Nothing added to zero gets nowhere; adding more zeros adds
nothing; nor climbs any genealogical tree. Something gets
added. Otherwise nature could not have made a man out of
a monkey or a mammal out of a reptile.
Novelties do get into life. Spinal column, prehensile tail,
blue eyes, were once novelties. There was a time when there
was no such thing as spine, tail, or eye, in any living being.
To say, as Davenport seems to, that they are not really
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THE EVOLUTION OF THE EARTH, LIFE, AND SEX
inherited but persist because parent and offspring are "chips
from the same old block," is to make the same "old block"
a Pandora's box.
Man's arm, bat's wing, horse's leg, whale's flipper, bird's
wing, and turtle's paddle, all evolved from the fin of a fish.
These are typical "adaptations"; they are characters which
have been acquired; whether "inherited" or not, they are
transmitted.
But they cannot be transmitted, said Weismann, because
the germ-plasm is sacred, immortal, and continuous; nothing
can get at it, nothing can touch it. Tennyson's immortal
brook had nothing on Weismann's germ-plasm. But that
brook does become a river; and somehow, some way, a piece
of the original life-germ, or germs, has come to be a human
being.
Biologically, immortality is a figure of speech, but based
on certain facts, namely: all living things grow, and if they
cannot grow young they grow old and die. Whatever
"immortality" is, then, it involves the process of either
remaining young or of growing young, "rejuvenescence."
Later, we shall see how man and higher animals renew their
youth.
Weismann's doctrine of the "continuity of the germ-
plasm" held sway for three decades, and still furnishes texts
for well-meaning enthusiasts who have a case to prove. It
is an especially useful ingredient in eugenic and political
pies. But as we shall see, there is nothing sacred about the
germ-plasm, nor is it alone allowed an immortal heritage.
Body cells also are potentially immortal. "Immortality" —
for germ-cells, for soma cells, for all living organisms — is
contingent upon an inherited mechanism and upon physical
and chemical conditions of environment.
The old formulae do not suffice to explain the facts of
evolution. The facts have outgrown the old theories. Evolu-
tion is up and down, back and forth; a circulating, pulsating,
inextricably woven web.
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WHY WE BEHAVE LIKE HUMAN BEINGS
We see life in fragments. Fragments, individuals, arise
by fission or reproduction from pre-existing individuals.
Each individual must be "adapted" to get food and oxygen.
Each individual strives to occupy the earth — as does oxygen
or hydrogen; in this it adapts itself to diverse conditions,
or it dies. Evolution proceeded not on one but on several
lines. The main lines led to food and oxygen, self -protection,
reproduction.
There are two great problems: how have individuals
become adapted to the conditions in which we find them?
Natural Selection seems to have been the limiting factor.
How have their organs become adapted to the functions they
perform? The Inheritance of Acquired Characters seems to
have been the decisive factor.
The great problem Darwin tried to solve was the origin
of species. There are species. Man is a species. The
gorilla is a species. How species arose is, after all, only
the problem of inheritance, of heredity, of individual varia-
tion, writ large. The more this problem is examined, the
less simple it seems. It is far from solved. Segregation is
an important factor; inbreeding tends to swamp variation.
Probably no one law can be formulated which will ade-
quately describe the processes of evolution. It is obvious
that if an animal is not fit to survive it will perish, and that
if there were no variations there would be no evolution.
Selection does work on variations — in nature as in Wall
Street; but as time goes on we shall probably hear less and
less of selection, variation, adaptation, etc., and more and
more of the nature of the physico-chemical mechanism which
exhibits living behavior under livable conditions. Under
such conditions living things do certain tilings, show a certain
capacity for a certain range of behavior. One of the striking
features of that range of behavior is the power to grow. In
fact, nothing so characterizes livingness as its capacity for
reproduction. This is so great in lower animals that they
are conceived of as endowed with immortality. With higher
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THE EVOLUTION OF THE EARTH, LIFE, AND SEX
animals "immortality" becomes a special affair of the so-
called germ-cells.
13
The very lowest organisms have nothing comparable to
sex. Woodruff's one-celled paramecium is in its 10,000th
generation. If each generation equaled man's, his original
Paramecium would now be well over a quarter of a million
years old. Yet it remains eternally young and shows no loss
of virility. As fast as one paramecium tires of existence it
renews its youth by becoming two, "which go on playing
the fascinating game of living here and now."
Some protozoa show the beginnings of sex. Two indi-
viduals unite (conjugate) to become one; nuclear material
is exchanged and divided: one becomes two again and these
two grow and divide. Conjugation is evidently a rejuvenation
process. Other protozoa only partially unite — and again
separate, "rejuvenated." In other species, a small individual
bores into and buries its body within that of a normal-sized
individual; the latter then divides repeatedly.
Thus far there is no division of labor or true sex forms.
When two unite the conjugation is an energy stimulus, as
though the spring of life needed rewinding. In higher organ-
isms, this rewinding becomes the prime function of the
sperm-cell.
In volvox, a high protozoon, thousands of cells held
together by protoplasmic threads unite into a colony. When
the colony is full-grown, certain cells become engorged with
food and are of great size. These big cells now divide into
many small cells, break away from the parent colony, and
form a little colony of their own, where they grow to full
size.
But in some volvox colonies, certain cells may divide and
form bundles of cells of rod-like bodies with whip-lash tails.
One of these now conjugates with a cell of the other type;
105
WHY WE BEHAVE LIKE HUMAN BEINGS
this then divides and founds a new colony. The cells of
the colony which were not concerned in reproduction live
awhile longer, and die.
Natural death had appeared. Also germ-cells: egg-cells;
sperm-cells. The idea of male and female began with a
volvox colony of protozoa.
The egg-cells of the volvox colony were large; the sperm-
cells, minute. This disproportion in size holds good for the
entire animal kingdom. The mammal spermatozoon may be
only l/100,000th part as large as the barely- visible-to-the-
naked-eye ovum.
One volvox colony may produce both ova and sperma, or
only ova, or only sperma. The volvox, therefore, is either
unisexual or hermaphroditic — it is neither male nor female.
As the ova themselves can form complete colonies witliout
the need of fertilization, the volvox is also parthenogenetic
(virgin-reproduction). In short, volvox, as Geddes says, is
an "epitome of the evolution of sex."
Many lower metazoa are so small that only with the
microscope can males be distinguished from females. There
is no mating, no sex complex. Ova and sperma are turned
loose to find each other as best they may; for every ovum
there are tens of thousands of sperma.
Higher in the scale, sex distinctions tend to be more pro-
nounced, but the evolution of sex forms does not follow a
straight line. Sometimes the sexual differences are unnotice-
ably slight; sometimes they reach absurd and amazing forms.
The difference between certain spider males and females is
equivalent to a man of normal size married to an eighty-foot-
high woman weighing a hundred tons. The female of one
species of worms is a hundred times larger than the male;
he lives in her oviduct as a parasite.
Difference between the two sexes is most conspicuous in
birds. But in rooks, kingfishers, and some parrots, there
are no secondary sex characters. Even many mammals show
none or almost none: mice, rabbits, cats. In vertebrates as
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THE EVOLUTION OF THE EARTH, LIFE, AND SEX
a whole, conspicuous sexual differences are the exception;
in the entire animal kingdom similarity is the rule.
Now from this brief resume of the history of sex let us see
what is back of it. Are sex and fertilization primary attri-
butes of life?
After years of study Woodruff concludes that "the proto-
plasm of a single cell may be self-sufficient to reproduce
itself indefinitely, under favorable environmental conditions,
without recourse to conjugation." In other words, the union
of two cells, or two organisms, is not the essential element
of new cells or organisms. Proper environment alone is
enough to enable the paramecium to reorganize its nucleus
and continue dividing indefinitely.
More suggestive is the behavior of simple planarian flat-
worms, studied for years by Child with interesting results.
Life processes in planaria are naturally highest at the head
and diminish toward the tail. Cut one into three pieces: the
head part grows a tail, the tail grows a head. Normally,
a head will grow at the end of the middle piece which was
toward the head, a tail at the other end. But Child can
reverse this! He can so alter the life process that a head
will grow out from the tail end, a tail from the head end.
The net result is the same: from one old worm, three new
worms. With no more "conjugation" or "fertilization" than
a scalpel.
What happens when the professor is not looking? At the
end of the season the old planaria break into bits. In the
spring, each bit grows into a new worm.
"Germ-cells" are not unlike these bits of worms; they
are not young but old cells. They become young by union.
In other words, the whole theory of the need of sexed parents
for carrying on the spark of life breaks up with planaria.
Even the theory of the need of special germ-cells to carry
on, falls flat. Any group of planarian body-cells is the
potential bearer of immortality.
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WHY WE BEHAVE LIKE HUMAN BEINGS
Loeb "fertilized" a frog's egg with a hatpin. Delage had
already found that starfish and other marine metazoa could
get along without fathers. Eggs could not only be fertilized
with various chemicals, but the developing embryos could
be turned this way or that, or checked in growth at different
stages, or be made to assume monstrous forms, or become
twins. With tannin and ammonia he not only "fertilized"
starfish eggs, but grew one with six rays — nature allows them
but five.
Among mammals, fertilization of ova from one species by
sperms from a closely allied species occurs. The hybrid
mule is sterile, but the hybrid offspring of a bull and a
buffalo is fertile. In lower vertebrates, and especially among
invertebrates, there are innumerable cases, according to Mar-
shall, where the sperms of one species can fertilize the ova
of other species.
Riddle's ringdove that laid eleven eggs and then began
to behave like a male, and was found, after an autopsy, to
have lost her ovaries through tuberculosis and to have devel-
oped male sex-glands instead, seems to indicate that neither
structure nor behavior has a fixed and uncontrollable basis
in heredity. The germ-cell chromosomes, or whatever it is
that makes for hereditary characters, can be modified and
even reversed.
For example, food may cause great change in structure.
Tadpoles fed on thymus gland become big, dark tadpoles —
but never develop into frogs; if fed adrenal gland, they
become very light in color. Larvae of bees fed royal jelly
become queens; on bee bread, unfertile females or workers.
Canaries fed on sweet red pepper become red in color. The
germ as the "bearer of heredity" is meaningless or monstrous
apart from its usual environment.
The egg is the parent of the chicken, and of more eggs.
What these eggs will develop into depends on many hitherto
unsuspected factors; as yet almost beyond control because
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THE EVOLUTION OF THE EARTH, LIFE, AND SEX
so little known. But among these factors is physical and
chemical environment.
A male element, as represented either by one of two
similar conjugating cells or by a distinctive sperm which
"fertilizes," is not a necessary factor in the reproduction of
life. But in truly bisexual animals fertilization is a life-
saving act, as Loeb calls it; if the germs are not fertilized,
they die. Fertilization also seems to be essential for
biparental inheritance.
No father, no inheritance from the father's side. Bisexual
reproduction made variation possible. Variation is newness.
Newness began with life when life was one-celled. That one
cell was both germ and body cell combined. It gradually
surrendered its functions to daughter cells. Some developed
capacities to high degrees; they are fit only for detailed,
specialized work. Some remained close to the primitive
original form. Groups of such primitive cells can renew
their vigor and begin anew.
But in the complex mechanisms of higher vertebrates, the
function of propagation came to be reserved for certain
cells. At the same time the struggle for life became keener.
The male element was a useful mechanism for novelties: it
doubled the chance for variation, it made it possible for the
organism to acquire something new. If the something new
was harmful, nature "selected" it for death.
The first business of sex, then, was to put new energy
into life, to release life, to keep it young and flowing. Sex
thus appears as one of the many adaptations whereby living
beings could become more highly organized and so carry on
on a higher scale. The development of special organs for
reproduction is comparable to the development of special
organs for digestion, for respiration, etc. It was not until
evolution was well advanced that the sperm or male element
assumed a share in the burden of heredity. This assumption
was a great step in the evolution of higher organisms.
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WHY WE BEHAVE LIKE HUMAN BEINGS
14
A fragment cut from a single-celled animal can move, but
cannot grow unless it contains part of the nucleus of the
animal. Every living cell (except red blood-cells) of every
living body, and every body of one cell, has a dense central
part, called a nucleus. No one knows just what the nucleus
is, but it is the essential part of all cells. A one-thirtieth
part of a sea-urchin's egg will live, grow, and develop into
a complete sea-urchin, if that thirtieth part contains a portion
of the nucleus. That thirtieth part of an egg is germ-plasm.
Any protoplasm is germ-plasm if it can grow a new
individual.
Ordinarily, cells divide by what is known as direct
division — a constriction appears at the middle of the cell,
increasing until finally the cell separates into two distinct
cells. But in fertilized ova, the division is indirect or mitotic
(thread-like).
As the nucleus seems to be the vital spot of the germ, and
as a certain part of it stains beautifully and so looms up
under the microscope, it is called chromatin (colored stuff).
No germ-cell divides until this chromatin performs. At first
a mere network, the chromatin becomes a long, continuous,
tangled skein. Then it breaks into bits, or units, called
chromosomes (colored bodies) ; they are always the same in
each species and vary in number from two to several hun-
dreds— six in mosquitoes, sixteen in rats, twenty-four in
mice, forty-eight in man, etc. Further, these units assume
definite shapes in different species, and are always in pairs.
Just outside the nucleus is a small granule called the
centrosome. While the chromatin is taking its definite thread
shape, the centrosome divides into two, which migrate to
opposite sides of the ovum. Meanwhile, the nuclear wall
disappears and its fluid mingles freely with the surrounding
protoplasm. From each centrosome spindles radiate out
toward the center of the cell. At this equator and to the ends
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THE EVOLUTION OF THE EARTH, LIFE, AND SEX
of the spindles the chromosomes now arrange themselves;
and divide — each chromosome splits lengthwise and becomes
two! The two sets of chromosomes now begin to withdraw
from each other toward the centrosomes.
Meanwhile, the round ovum begins to lengthen, then begins
to constrict at the equator. The chromosomes begin to
increase in size until each becomes as big as the parent
chromosome. The spindle fibers disappear. A wall begins
to form around the chromosomes. The cell's equator has
grown, smaller; it is an hour-glass form. It breaks in two.
The one ovum has become two cells. The chromosomes
again become mere chromatin, vaguely seen in the dense
mass of the nucleus, for the surrounding wall is now
complete.
What was one is now two, each complete: blob of proto-
plasm, nucleus, everything. The most wonderful thing in
the world. It is potentially a full-grown animal, complete
unto itself. All it needs is food and safety.
That is the way we grew up: one cell became two, two
became four, four . . .
The oocytes from which ova develop, and the spermato-
gonia which become sperms, are present at the time of birth.
Although they are among the last of the cells of the body lo
mature, they are set aside early in embryonic development.
The big difference between sperm and ovum is size and
behavior. The ovum has much protoplasm and no means
of locomotion. The sperm is all nucleus — except its long
tail of cytoplasm, as protoplasm outside the nucleus is called.
By this whip-lash tail it travels.
Before the parent sperm and ovum unite, they go through
a maturation or ripening process vv^hereby the number of
chromosomes in each germ-cell is cut in two. The fertilized
human ovum thus starts with the original number of chromo-
somes— forty-eight, half being contributed by each parent
germ-cell. The maturation process is in general like that
of ordinary division by mitosis. But the chromosomes unite
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WHY WE BEHAVE LIKE HUMAN BEINGS
in pairs; thus, one of each paired unit passes to each cell
formed by the division.
During fertilization the head and "middle piece'' of the
sperm enter the ovum, the head being equivalent to the
divided nucleus of an ordinary cell in process of mitosis.
The middle piece becomes the centrosome — in maturing, the
ovum lost its own centrosome. It is this new centrosome that
divides as above described, each new body taking position
as in ordinary mitosis. The chromatin of the two nuclei
now splits into chromosomes, etc. What was a fertilized
ovum is two cells. The development of a rat, an elephant,
or a human being, has begun.
The fertilized human ovum has forty-eight chromosomes,
twenty-four from each parent germ. Here is where heredity
is supposed to get in its work, and Mendel's law is supposed
to preside over the cutting of the inheritance.
15
We all inherit something, if only crooked legs or a
tendency to twins. And we all have ancestors: in fact, a
surprising number if they had not intermarried. Reckoning
three generations to a century, each of us to-day is entitled
to 120,000,000,000,000 lineal ancestors in A. D. 1. They
intermarried. At no time has this earth seen 120,000,000,000
people, much less 120,000,000,000,000. Kaiser Wilhelm
had 162 ancestors ten generations ago — ^he was entitled to
512. All Anglo-Saxons are at least thirtieth cousins.
We have ancestors. We inherit features, traits, characters,
peculiarities — marks of individuality whereby each of us is
not only a separate entity, but different in detail from every
other individual on earth.
How do we get these traits? What traits are heritable,
what are not? The game of heredity was evolved to answer
these questions. The game presupposes a knowledge of
germ-cell division, a speaking acquaintance with chromo-
112
THE EVOLUTION OF THE EARTH, LIFE, AND SEX
somes, the assumption that they are made up of countless
distinct and definite chromomeres, and faith in two theories —
germ-plasm, eternal and inviolable; chromomeres, the "ulti-
mate" bearers of heredity. Thomson recommends also two
ordinary packs of playing cards from which the kings have
been removed. Why kings is not explained. Each is now
a short deck — forty-eight cards. How many chromosomes in
the human body? Forty-eight.
We inherit twenty-four maternal and twenty-four paternal
chromosomes: possible permutations, 16,777,216. That is
nothing. That only refers to possible permutations for one
single specific pair of individual germs. Counting potential
germ capacity for the life of one pair of parents gives us
the tidy range of total possible different combinations in all
the fertilizable ova as 300,000,000,000,000.
Now imagine that we deal not with a mere forty-eight-
chromosome permutation system, but with forty-eight chromo-
somes each consisting of "countless" chromomeres, each a
possible bearer of heredity! In that case, as Thomson says,
every human germ-cell would be "absolutely unique"— and
undoubtedly is.
Some biologists play this game because they feel impelled
to have a frame on which they can hang heredity. They are
not agreed as to what heredity is. But there are the "colored
bodies." They do not know what they are. All right. Hang
heredity on them. Solve the mystery by multiplying it by
forty-eight unknowns.
What is heredity? Heredity is germ-plasm. How does
heredity work? By the beads on the thread of chromatin.
Maybe. Maybe heredity counts its beads: one bead for
each generation. The question is: does this hypothesis get
us farther into life than Darwin's "gemmules" or Weismann's
"biophores"? I do not see that it does. It does seem to
get us in deeper.
Now for the "traits." Are you a female? It is a "Men-
delian" trait. Are you bald-headed? See Mendel. Are
113
WHY WE BEHAVE LIKE HUMAN BEINGS
your fingers all thumbs? "Mendelian" dominance. Daven-
port, specialist in heredity, no longer finds anything mys-
terious in the sudden appearance of atavistic characters. We
are full of such "grandpa" characters: they are "latent";
they appear according to Mendel's law of heredity. Mendel
would be surprised if he could come back!
Gregor Mendel was a monk, lived in a cloister, taught
school, and had a hobby — ^garden peas. He died in 1884
at the age of sixty-two, and was promptly forgotten. Wliat
he found out about peas and buried in a little article in
1866 was not discovered until 1900 — the world had been
too busy with Darwin. What this discovery started is still
going. Mendel is less abused to-day than Darwin; some
think he made a greater discovery. He certainly is a cult.
Walter thus formulates Mendel's "law": "When parents
that are unlike with respect to any character are crossed,
the progeny of the first generation will be like the dominant
parent with respect to the character in question. When the
hybrid offspring of this first generation are crossed with
each other, they will produce a mixed progeny: 25 per cent
will be like the dominant grandparent; 25 per cent like the
other grandparent; 50 per cent like the parents resembling
the dominant grandparent."
And plenty of stufi"ed mice and guinea-pig martyrs-to-
science in museum cases prove that Mendel's law works. It
stands on three legs:
1. Independent unit characters. While we inherit a gen-
eral plan of structure, we inherit details, or traits, as "inde-
pendent units."
2. Dominance. Brown eyes marry blue: offspring all
brown-eyed. Brown is a positive character, dominant; blue
is negative, "recessive." By the fact of its dominance, brown
appears. The blue may be present in the germ-plasm, but
as long as the "determiner" is also present, blue will be
unable to show itself. "Unit" characters are inlierited
through "determiners" in the germ-plasm.
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THE EVOLUTION OF THE EARTH, LIFE, AND SEX
3. Segregation, or purity of the germ-cells. A sperm cell
or an ovum can have only one of two "alternating char-
acters." For example, either blue-eyed or brown, but not
both. Cross a blue-eyed with a brown-eyed: the fertilized
ovum will contain both blue and brown units; the offspring
will be brown-eyed; brown is the determiner. But half this
offspring's germ-cells will possess the blue-eyed unit; half,
the brown-eyed; no one germ-cell will have both. The "alter-
nating" characters will have been segregated.
This segregation of alternate characters was Mendel's chief
point. The way the chromosomes divide in the maturing
germ-cell seemed a good machine to try it on. Investigators
began to count chromosomes, and on each hang a "unit"
character. As there were more "units" than chromosomes,
they postulated chromomeres. As these could not be seen
and so checked up, they could postulate as many as they
wanted.
But experiments show much conflict, nor are experimenters
agreed as to results or general conclusions. They can rarely
know, if ever, whether the stock is "pure," a hybrid, or a
blend. New "Mendelian" factors have been added: "com-
plementary," "supplementary," "inhibitory," "cumulative,"
"lethal." "Units" may be "independent" as to quality or
as to quantity; or a unit may function by being "absent"!
A "dominant" character that performed true to form for
three generations practically gave up in the seventh genera-
tion ; showing a discrepancy between man's and nature's idea
of "dominance." There seems often no real stability in the
parent type. On cross-mating it breaks down ; the component
characters recombine into different or new types.
If man bred as fast as mice and guinea-pigs, we should
know more about our own Mendelian "units" than we do
now. Enough is known, however, to support a Eugenics
Society. Its motto is: When in doubt, marry a dissimilar;
you may thereby skip a generation with a wooden head.
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WHY WE BEHAVE LIKE HUMAN BEINGS
16
Can we control our own evolution? Do we want to? To
what end? In which direction? Presumably we could; and
this is as far as eugenics has any standing in a court of
science. All the rest of eugenics is politics — based on
assumptions open to opposite views or on race prejudice pure
and simple.
Man could probably breed a race of human beings with
the following "traits": bald, fat, long chest, short and
crooked legs, left-handed, six-fingered and all fingers thumbs
and webbed, near-sighted, deaf and dumb, feeble-minded,
curly haired, cataract, albino, long-lived, and prolific, with
a tendency to twins; at any rate, these are a few of the many
so-called Mendelian traits capable of transmission. There
are said to be at least thirty-four different hereditary eye
defects alone, eight of which can produce blindness.
With nothing more to work with than normal variation in
wild rock pigeons, man has bred over twenty races of pigeons.
What could he not do with the human race if ... ! The
"if" introduces politics. And to "breed" a race of humans
involves a decision as to what is desirable; a thousand-year-
long dynasty of cast-iron despots with such power over sub-
jects as Herod never hoped for or breeder of slaves dared
exercise.
What are we to breed at? What is the new race to go in
for? Stature, tow hair, blue eyes, eight fingers, toothless, one
toe, fecundity, mental precocity? The list of heritable traits
is indefinite. "Marry dissimilars" is probably good eugenic
advice if we are not bent on handing down our own personal
traits — but most people are satisfied with their traits. At
any rate, the sex impulse itself generally chooses its mate,
and that impulse is not primarily concerned in offspring.
Take stature. If height is the criterion for desirable citi-
zens, early-and-often marriage should be encouraged in Iowa,
Kentucky, and Missouri; made late and rare in New York,
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THE EVOLUTION OF THE EARTH, LIFE, AND SEX
Pennsylvania, and Massachusetts; and prohibited in Rhode
Island. Meanwhile, close Ellis Island to all but native Pata-
gonians.
What shall we do with the Attic Greeks? Raise their
"quota," or exclude them because they do. not look like the
Harvard graduate who fathers an average of only three-
fourths of a son and the Vassar graduate who mothers one-
half of a daughter?
If there is anything in the "continuity of the germ-plasm"
theory, there should be some good germs left in a country
which in 150 years produced such statesmen as Miltiades,
Themistocles, Aristides, and Pericles; such poets as Aes-
chylus, Euripides, and Sophocles; such scientists as Socrates,
Plato, and Aristotle; such artists as Phidias and Praxiteles;
such historians as Thucydides and Xenophon ; such orators as
Aeschines, Demosthenes, and Lysias. The whole earth, in no
centuries before or since, declared Galton, produced such a
galaxy of illustrious men.
Some of that germ-plasm may be blacking boots to-day
on a Staten Island ferry or running a short-order restaurant
in El Reno. Who knows? One thing is certain: if it is, it
is more interested in a short shine or a long order than it
is in eugenics.
Could anyone, even Francis Galton himself, from the hill
behind Athens in the year 600 B. c, have predicted that within
a hundred years the little Rhode-Island-sized state of Attica
would begin to bud genius so fast and so big that the world
has not stopped wondering about it yet?
Could Galton have predicted Lincoln? Could Ellis Island?
Can Ellis Island spot the Jukes from the Altmans, or have the
faintest idea when it holds up a Steinmetz — or an Edward
Bok?
The Jukes case is notorious — and illuminating, and was
thoroughly investigated by Davenport. The case began about
150 years ago with a lazy, mentally defective "Max" who
settled not far from New York City. His two sons married
117
WHY WE BEHAVE LIKE HUMAN BEINGS
into a family of six sisters, all harlots. One of them was
known as "Margaret, the mother of criminals."
Of the 2,094 progeny of the Jukes sisters, 1,258 were liv-
ing in 1915: 65 were "good citizens"; 600 were feeble-
minded and epileptic. "Criminal," "harlot," "mentally de-
fective," "drunkard," "pauper," recur in their records again
and again; now and then, "murderer." In seventy-five years
alone, Max's feeble-minded pauper progeny cost New York
State a million and a quarter of dollars.
Looks like a plain case — segregation or a surgeon. And
yet a Jukes's descendant may be a governor and several of
them may be in Congress. Some say they are. Conceivably,
a Jukes might become a second Pasteur — and save more lives
than were lost in the World War. This is certain: the state
or nation which permits marriage between mental defectives
and deaf mutes will have to provide for deaf mutes and
feeble-minded. We may improve the breed of figs and eradi-
cate thistles, but never will we gather figs from thistles or
good figs from poor fig stock.
What carries eugenics into politics is that the Jukes are
neither figs nor thistles, and we do not yet know just how
feeble a mind has to be before it has to be locked up to pro-
tect those who have minds and refuse to use them.
Many Jukes have too much brain to be segregated, not
enough to carry a rifle to the front. Selection. That kind
of selection is a modern specialty. The sound-minded able-
bodied get shot, the priests and scholars will not marry, and
the ambitious women and the selfish men transmit their
names but not their germs.
Is civilization now breeding a "pure" Andy Gump type —
no teeth, no lower jaw? Cigarettes may save the lower lip,
and chewing gum may save enough of the lower jaw to sup-
port a chewing gum. But a full and sound set of teeth these
days is about as primitive as is a perforated olecranon fossa
of the humerus.
Natural selection is always at work. In every million
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THE EVOLUTION OF THE EARTH, LIFE, AND SEX
births, not counting stillborns, there are 2,687 deaths the
first year from congenital malformation. A certain other
small percentage who can never be happy or useful, are
nursed along for a varying number of years. This fraction
is undoubtedly larger in civilized than in natural conditions;
it is probably increasing. It offers a social and biologic
problem. That problem is not likely to be solved in the near
future because we have too many abstract formula? about
humanity and too little common sense for solving concrete
social problems.
But the "racial purity" and the "racial inferiority" behind
such books as McDougall's Is America Safe for Democracy?
Chamberlain's Foundations of Nineteenth Century Civiliza'
tion; Grant's The Passing of the Great Race; Wiggam's The
New Decalogue of Science; Gould's America a Family
Matter; and East's Mankind at the Crossroads, are bunk pure
and simple. If these United States wish to restrict immigra-
tion to "Nordics" or to this or that political group, why not
say so and be done with it? To bolster up racial prejudice
or a Nordic or a Puritan complex by false and misleading
inferences drawn from "intelligence tests" or from pseudo-
biology and ethnology, is to throw away science and fall back
on the mentality of primitive savagery.
Evolution produced a human brain, our only remarkable
inheritance. Nothing else counts. Body is simply brain's
servant. Treat the body right, of course; no brain can func-
tion well without good service. But why worry more about
the looks, color, and clothes of the servant than the service it
performs?
119
CHAPTER III
THE PROCESSES OF LIVING AND THE GERMS OF DISEASE
J. Life Is Change and Requires Energy. 2. The Body Is a Living Machine.
3. It Requires Calories. 4. Why We Must Digest Food. 5. The Digestive
System. 6. Our Daily Bread and Water. 7, Seeing Food Through the Canal.
S. How Food is Absorbed. 9. The Flesh Is in the Blood. 10. How the
"Flesh" Is Transported. 11. Giving the Blood the Air. 12. The Great Blood
Purifier. 13. The Red Blood-Cells. 14. The Body Thermostat. 15. The Role
of the Duct Glands. 16. The "Little Fleas." 17. The Deadly Germs.
1
All change implies resistance overcome, work done, en-
ergy. Energy is ability to work. Without energy there is
no work done or change in any living being. Change in liv-
ing beings takes many forms. Growth, maintenance, repair,
regulation, secretion, chemical synthesis, muscular activity,
contraction and relaxation, heat production — all these are
changes, living processes. They require energy.
Energy required for engines is stored in fuel — organic
compounds such as coal, wood, oil, etc. Energy used for
life processes is also stored in fuel — organic compounds fed
into the body as sugars and fats. Most of our food is physio-
logical fuel. This fuel is "burned" in the body, releasing
energy. This burning is called oxidation. Our vitality can
be measured by the rate of oxidation. When oxidation ceases,
animation ceases. Even individual cells die when deprived
of oxygen. In dividing cells the rate of oxidation is speeded
up.
Oxidation is a chemical change and takes place only under
certain conditions, temperature, etc. During oxidation heat
is released, as it is every time we bat an eye, lift a finger, or
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THE PROCESSES OF LIVING AND THE GERMS OF DISEASE
think; batting an eye, lifting a finger, and thinking are forms
of work, energy-consuming processes.
What is oxidation? It can be seen in a furnace; it has
never been seen in a living organism. But during oxidation
something becomes something else, presumably by means of
an ion or carrier of a charge of electricity; something in-
creases its electrical charge; the electrical charge of some-
thing else decreases; oxygen unites with something else, form-
ing an oxide. We constantly exhale carbon dioxide — the end-
product of the oxidation of carbon. Heat is always liberated
during oxidation; our exhaled air is always warm air.
Our viscera consume much energy in capturing oxygen and
in converting foods into physiological fuel, especially into
a sugar called glucose, or when stored in the liver, muscles,
or other tissues, called glycogen. Stimulate the splanchnic
nerve with electricity, and the liver will convert glycogen to
glucose — by hydrolysis; rearrange the molecules of glucose,
it becomes lactic acid, which by dehydrogenation becomes
pyruvic acid. This, oxidized, becomes acetaldehyde. This,
oxidized, becomes carbon dioxide and water — materials to
be eliminated from the body that plants may reincorporate
them into sugar-cane or grapes or potatoes.
When man digs up the potato, the "potato" that is in his
arm as glycogen is oxidized, but only partially. The fate
of the lactic acid that is left over is not quite known, but
oxidation processes are known to be involved.
What is oxidation, then? Every process involved in digging
up potatoes or in thinking about potatoes. Potatoes them-
selves are stored energy. Cut one open; it turns black — •
that also is oxidation.
A helping of mashed potatoes contains enough energy to
raise the temperature of about 400 pounds of water about
two degrees, or to enable a man to sweat enough to keep his
body cool for one hour's work digging potatoes.
The potatoes carried to the cellar will lie dormant, if the
cellar is not too warm and damp, until the following spring.
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WHY WE BEHAVE LIKE HUMAN BEINGS
Then, cut into bits and put into warm, moist ground, they
will begin to grow. Each "eye" of each potato will grow;
it is a "germ." Every living germ, whether plant or animal,
contains enough stored energy to enable it to respond to
vital situations. In its responses or actions it will capture
more energy. The capacity of growing things for work is
perhaps the most astounding phenomenon in the universe.
Growing trees can split rocks with their roots and lift tons of
matter hundreds of feet above the ground. Swelling peas in
an iron pot lifted a cover weighted with 160 pounds.
Now here is a curious thing. The potato digger dies when
his heart stops beating. He is dead; but millions and millions
of cells of his dead body will remain alive for hours — they
have not yet exhausted their oxygen and fuel. Aseptically
removed from the body and kept moist on ice, some tissue
cells will remain alive for ten days. If placed in a certain
solution and oxygen, their life can be prolonged indefinitely.
Connective tissue cells have been cultivated for years. All
they seem to require is proper environment. Their capacity
to live and multiply outside man's body has opened new
conceptions of life.
Life is a dynamic relationship between structure and en-
vironment. We do not live long when the oxygen of our
environment is shut off. The faster we live, the more oxygen
we require. When our reptilian ancestor improved the
mechanism begun by amphibia for capturing oxygen from
the air instead of from the water, an enormously important
step in life was made. When our mammalian ancestor, by
supplying a diaphragm, perfected that mechanism, breathing
became a delight and oxygen easy to get. Fast living became
possible. But whether we live fast or slow, and whether we
work with our hands or with our brains, or do no work at
all, our living body must work to keep alive. We must have
energy. We cannot get it from an electric current, we can-
not get it from mere gravity, we cannot get it from the rays
of the sun as plants can, but get it we must or die. As our
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THE PROCESSES OF LIVING AND THE GERMS OF DISEASE
bodily mechanism and all animal bodies are internal-com-
bustion engines, we get our energy from the oxidation of
foodstuffs converted into physiological fuel. The capture
and transformation of energy is the most fundamental of all
living processes. How food and oxygen are made available
for consumption in our growing-going bodily mechanism is
a process of fundamental importance.
2
When we finish our day's work, we walk to our car and
drive home. (We may have no car: we allow ourselves one
for purposes of illustration.)
The motor-mechanism with which we walk to our car
weighs about eighty pounds : sixty of muscle, twenty of bones.
With every step we take, about 300 muscles are in action.
Only as muscles contract and relax can we move. By con-
tracting, muscles shorten — they do not push, they pull. The
bones support the muscles, the muscles move the bones as
levers.
Muscles are in opposing groups. With a certain group we
turn our head; mere relaxing of this group will not restore
the head to its original position: we must use the other group.
To balance our head on our spine, we use 20 muscles; to
balance our spine with each step, 144 muscles.
Muscles are engines, each made up of hundreds of thou-
sands of tiny individual muscle-cell engines. With each step,
over one hundred million engines are at work.
When muscle responds to stimulus of nerve or electrode
of an induction coil, lactic and perhaps some other acid
is liberated from some compound in the muscle itself. This
reaction changes the hydrogen ion concentration in the muscle
cell; it contracts, shortens. Some of the lactic acid is oxi-
dized and heat is formed, the remaining lactic acid is re-
stored to the compound from which it was used. Meanwhile,
the glycogen stored in the muscle has been called on to supply
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WHY WE BEHAVE LIKE HUMAN BEINGS
the energy of the transaction. With the disappearance of the
lactic acid, the muscle returns to its former resting condition;
it relaxes. All this takes place in all the half -million or
more muscle cells of every single muscle involved.
Microscopically small blood vessels bring oxygen and
fuel which is "burned" with the aid of oxygen, without
which there is no combustion in muscle or auto engine. Micro-
scopically small veins carry away the products of combus-
tion, the same in muscle as in the auto engine — ^water and
carbon dioxide. In the kidneys the blood is relieved of the
water; in the lungs, of the carbon dioxide.
The blood itself is driven about by the heart, an engine of
such tiny muscle engines so fused together that they cannot
be teased apart with the finest needle. Marvelous it is that
the heart knows how fast it must do its work if it is to give
adequate service. While quiet at our desk, the heart pours
about five pints of blood into our aorta every minute. Wlien
we run uphill, the heart will drive blood into the aorta seven
times that fast — thirty-five pints a minute! And from the
great aorta the blood will be carried to every one of the
millions of millions of cells in the body. Wherever the body
is scratched, wherever the mosquito dips his bill, there blood
is found.
Running uphill requires much energy: much sugar is oxi-
dized, much carbon dioxide is generated. Hence the faster
heartbeat, to hurry the blood to get more oxygen and fuel,
to get rid of more carbon dioxide. The extra sugar needed
is picked up from the sugar-bin in the liver; the oxygen is
got from the lungs. While the red blood-cells are reloading
oxygen from the six million air-sacs in the lungs, the blood
itself is giving up its excess carbon dioxide.
These air-sacs are always ready to do their duty. That is
why the bellows moved by twenty-four levers of bone must
work faster in uphill work; they must keep the air in the
lung air-sacs constant; not have more than 5 per cent of
carbon dioxide. But as running uphill burned up seven
124
THE PROCESSES OF LIVING AND THE GERMS OF DISEASE
times as much fuel as sitting at rest, there was seven times
as much waste product of combustion to be got rid of. That
makes us "pant": our bellows work faster and keep up the
pace until the normal proportion of carbon dioxide is re-
stored in the little air-sacs.
We need about thirty ounces of fuel a day to keep our
body machine in good trim. The combustion of that fuel
makes just the same amount of heat in our body engines as if
burned in any other engine. In fact, so much of our fuel
goes into heat that if we could not get rid of the surplus gen-
erated in running or in any hard work, our blood would
jell.
One ameba has been seen to chase another ameba, catch
up with it, begin to swallow it, lose it, chase it again, recap-
ture it, lose it, chase it, capture it, and "swallow" it: by flow-
ing around it and thus inclosing it within its own body. By
and by the little cannibal opened up its body and moved away
from the debris of the dead ameba. A little later it divided
and then there were two. (Few of us can do more than
that in a day — some do less in a lifetime and leave nothing
behind but the debris of their dead protoplasm.) That ameba
has no liver, no alimentary canal, heart, lungs, gills, or
mouth. Yet in that little body of one cell every essential
phenomenon of life takes place. It functions, even as a
human being.
The difference between ameoa and man is not unlike that
between a tiny motor-boat and the biggest ship afloat. Man
has more parts, the parts are vastly more intricate. He carries
a heavier load, moves faster, goes farther.
All this requires great energy. But we no more make
energy than a motor or a dynamo. We must capture it first,
then convert it. Every move we make, every word we speak,
every thought that passes through our brain, every beat of
our heart, every breath we draw awake or asleep, requires
energy; and all the while we must run a refrigerating plant
or boil over, and a heating plant or freeze to death. Our
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WHY WE BEHAVE LIKE HUMAN BEINGS
motor mechanism must be oiled at every point of friction.
Our nervous system must be protected, cleaned, and kept in
repair. Because we are fearfully and wonderfully made, we
must have much energy merely to keep alive.
But as long as we are alive, and whether afoot or on
horseback, awake or asleep, we are going machines: the
chest rises and falls, the heart beats, the blood circulates,
metabolism goes on, life functions; energy is required. But
however energetic we may feel, we cannot will our heart to
stop beating or commit suicide by holding our breath; we
may hold our breath long enough to lose consciousness: our
lungs then will resume rising and falling. Back of conscious
effort, and so well organized that conscious effort may be
dispensed with, is a human body which functions as long as
it is fed and can maintain itself in a state of dynamic equilib-
rium.
Our inheritance seems to have set a limit to the duration
of that equilibrium. To discover its nature and how to main-
tain it is the great problem. Now that we have ceased to
be merely objects of religious superstition or of philosophic
speculation, we can take our lease on life into a court where
it can have a fair trial. That court has already solved great
problems formerly held in awe and garbed in mystery. There
is no known inherent reason why the problem of dynamic
equilibrium in living organisms should not be solved.
The ameba solved it; man solves it for fragments (the
germ-cells) of his body. Even tumor cells are potentially
immortal. Much, if not all, of the tissue of our body is
potentially tumor. If ameba solved it, why not man?
The goal is such knowledge of the living that disease may
be prevented and the grave robbed of its victory. W^e of this
generation shall not attain that goal, but it is a goal toward
which humanity may turn with much hope and some confi-
dence. Meanwhile, there is the immediate problem of hang-
ing on to such lease of life as has been bequeathed to us.
As a nation with unlimited resources and as a race with large
126
THE PROCESSES OF LIVING AND THE GERMS OF DISEASE
brains, we abuse our lease of life, often with fatal results.
Many preserve their strength merely to make their lungs
breathe and their heart beat. The evolution that ended with
reptiles sufficed for such processes; human brains were
evolved for higher forms of life.
3
You may be growing: you require food to build up tissue.
You may be going: you require energy. Both growing and
going are change, metabolism. But building is an assimila-
tion process; you construct or repair something: that is con-
structive metabolism, or anabolism. But the exhibition of
energy involves dissimilation; by converting complex sub-
stances into simple ones you destroy something: that is de-
structive metabolism, or katabolism. In both metabolic proc-
esses there is a residue: husks not used in assimilation, others
left from the destruction. These are excretions and must
be eliminated from the body.
Our energy is derived from fuel in the form of food. Our
daily fuel needs vary according to our age, size, sex, and
especially the amount of energy we expend. A lumberjack
expends more energy than a lounge-lizard.
A pound of sugar burned in our body yields as much heat
as a pound of sugar burned in a chemical oven. Heat is a
form of energy, and when measured in units required to
raise the temperature of one kilogram (about two pints) of
water from 0° to 1° Centigrade (about 2 degrees), is called
a calorie^ or "great calorie."
Sugar burned in our body makes energy available. Of
such fuel we normally have in reserve and stored in muscles
and the liver about ten ounces, or 1,200 calories. That is
potential energy. Suppose we burn it, as we do when chop-
ping wood; how much energy would we get? Enough to lift
a weight of one hundred tons to a height of three feet. That
is our normal potential energy reserve.
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WHY WE BEHAVE LIKE HUMAN BEINGS
To do nothing, just to keep alive, quiet, flat on our back, we
require about 1,700 calories a day, enough to lift nearly
two hundred tons one foot. That amount of energy goes
into heartbeat, breathing, keeping the body at a constant
temperature and alive. It is called basal metabolism.
The energy consumption, in calories, per kilogram in
doubling the birth body weight is: colts, 4,512; lambs, 4,243;
kittens, 4,554; babies, 28,864. It is biologically significant
that the child of man requires six times more energy to
grow a pound than a calf does. And for every calf of stunted
growth in the world there are 600 stunted children! Basal
metabolism, as we might expect, is highest in childhood. After
the fifteenth year it drops sharply to twenty, thereafter it
slowly declines throughout life. The growing body stores up
energy in the form of new tissue.
We eat a meal; digestion is metabolism also, work. For
the work of digesting a meal, 170 calories must be added to
the 1,700 needed for basal metabolism. Reading is work:
for two hours, add 10 calories more; for a five-mile walk or
two hours at golf, 300 calories; for twelve hours swivel-chair
work (mostly expended in muscle work in holding the body in
the chair), 250 calories. Total, 2,450 calories; or say 2,500
for an average man. In a body completely relaxed but with
the brain actively at work, so little extra energy is consumed
that the calorimeter cannot find it! The more active the work,
the more calories required. A farmer will use up 1,000 more
calories a day than a bookkeeper. A lumberman may use up
7,000 in one day; a six-day bicyclist, 10,000.
Food consumed in excess of energy required is stored as
fat: under the skin, around the abdomen, between the muscles;
but not in the more active tissues — even a "fat-head" has
little fat in his brain.
Du Bois points out that when a man has maintained a
weight of 165 pounds for twenty years — as many do — it
means that of a total consumption of 18,250,000 calories he
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THE PROCESSES OF LIVING AND THE GERMS OF DISEASE
has not stored or lost more than 9,300, enough calories for
two pounds of fat — "an exactness equaled by few mechanical
devices and almost no other biologic process." But suppose
a man of 165 pounds doubles his weight in twenty years;
that means that he has added 22 pounds of fatty tissue and
133 pounds of fat. And one small extra pat of butter a day
will do it; there is enough energy in that pat of butter to
walk one and one-third miles. As Du Bois says, he ate
eleven grams too much butter, or walked one and one-third
miles too little.
Sitting up in a chair is work: muscles are contracted,
energy is liberated as heat and as work performed. Both
can be measured in calories, the work calories in terms of
the mechanical equivalent of heat. This has practical value.
A machine that develops three heat to one work calorie is
25 per cent efficient. Muscles holding up the body in a chair
develop three heat-calories to one of work. Our muscles are
about 25 per cent efficient. But a trained muscle is 40 per
cent efficient. A habitual chair-worker requires less energy
to sit still than does one accustomed to being on his feet.
Some men find sitting in a chair for any length of time really
hard work.
Two men at the same work, blow for blow, stroke for
stroke, step for step : one sweats ; the other is cool as a cucum-
ber. One was not used to it, was not trained; many of his
calories went into heat. The other was trained, it was his
steady job; he got more work out of his calories.
To get more work out of our calories is to function better.
To function better is to live longer. If we find that the thing
we trust to pick the mother of our children is simply a double-
barreled pump, knowledge of our heart or the liquid refresh-
ment it pumps to our brain will not grow more nerve cells,
but it should make us less nervous and more respectful of
the pump and the refreshment it delivers; when it stops, the
brain starves to death.
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WHY WE BEHAVE LIKE HUMAN BEINGS
4
Water, carbon dioxide, and nitrogen made life possible.
Bacteria make plants possible. Plants make animals pos-
sible. Did it ever occur to you that, apart from a few but
necessary mineral salts, everything we eat is or has been
alive? About 50 per cent of our body is carbon. We are
oxidizing carbon every moment of our life. We must have
carbon. We can eat lampblack, charcoal, and diamond dust
(all carbon) ; we cannot digest them. Anything we eat and
do not digest remains a foreign substance that must be elimi-
nated. There is carbon dioxide in the air we breathe, but we
cannot build the carbon of that compound into our body or
burn it for its energy with the aid of the oxygen of the
water we drink. In short, we are dependent on shoddy,
second-hand material. Plants are closer to Nature and not
so dependent.
To photograph is to light- write; to photo synthesize is to
light-put-together. With sunlight through a green filter called
chlorophyl (green-leaf) plants decompose the carbon dioxide
of the air and combine its carbon with the oxygen and hydro-
gen of water to make carbohydrates (carbon-water), so named
because they always contain hydrogen and oxygen in the same
proportions as they are found in water — twice as much hydro-
gen as oxygen.
The simplest carbohydrate is sugar. But sugar is soluble
and easily washed away. When plants need to store sugar,
they change it to a starch. Starch is a more complex sugar,
same kind of atoms but combined into different molecules.
By further combinations of the same elements, plants form
fats or oils. Plants can synthesize sugars and fats because
water of soil and carbon dioxide of air are available and
because plants can use the sun's energy through their photo-
synthetic power. If the plant had not thus made carbon fit
to eat, this earth would be a No-man's land. Ninety-five
130
THE PROCESSES OF LIVING AND THE GERMS OF DISEASE
per cent of the materials of our body are made available
by plants' photosynthetic power.
Another 2 per cent of us is nitrogen — small but important.
There is no flesh and no protoplasm without nitrogen. The
air we breathe contains nitrogen, but we can no more use it
than we can the carbon dioxide of air. We get our nitrogen
also from plants, or from animals which originally got it
from plants. Foods which contain nitrogen are proteins
{protos, first) or nitrogenous foods.
Proteins, while enormously complex, are only compounds
of the same three elements found in sugars and fats plus nitro-
gen and mineral salts. Here is where bacteria come in.
Plants can fix their own carbon, but they must go to bacteria
for their nitrogen. As a dead horse contains more nitrogen
than an acre of wheat, his nitrogen must be kept in circula-
tion. Bacteria do the work. They are the "middlemen of
the nutritive chain."
In one gram of soil, says Jordan, the following bacteria
have been found: peptone-decomposing, 3,750,000; urea-de-
composing, 50,000; denitrifying, 50,000; nitrifying, 7,500;
nitrogen-fixing, 25. Just how bacteria wreck a dead horse
is not known, because so little is known as to the structure
of the protein molecule. But "eventually, out of the seething
caldron of molecular disintegration, emerge such relatively
simple bodies as organic acids and amins, mercaptan, sul-
phuretted hydrogen, carbon dioxide, and ammonia."
The ammonia may be oxidized to nitrites, and the nitrites
oxidized to nitrates. This is nitrification, and enormously
important for the food supply of the world; otherwise, the
ammonia from decaying plant life and from manures would
not be available for living plants. Sulphur bacteria change
the sulphuretted hydrogen of mineral springs and decaying
tissue to sulphur, which oxidizes to sulphuric acid. This,
uniting with certain other substances, forms sulphates; in this
form plants can build them into tissue. The nitrogen-fixing
bacteria get their nitrogen direct from the air mixed in with
131
WHY WE BEHAVE LIKE HUMAN BEINGS
the soil. They make their home in little nodules of the roots
of such plants as clover and beans, and by enriching the soil
with nitrogenous compounds make higher plant life possible.
Bacteria are also the great scavengers of the sea, turning
loose carbon dioxide, ammonia, and ammoniate materials
which algae build into food compounds which make higher
sea life possible.
Thomson relates how boxes of mud and manure were set
alongside a fish pond which was about to give out. Bacteria
multiplied, making food for tiny protozoa. These overflowed
into the pond and were eaten by tiny Crustacea and similar
small fry. There was now food for fish. They multiplied,
and were eaten by man. Fish is said to be food for brains.
It is not. But what looked like mud became part of man.
And at last man used his brain, invented a microscope, dis-
covered bacteria, and opened a new account with life.
To return to our mutton. Plants find nitrates in the soil,
also sulphates and phosphates. These they combine with
the elements they photosynthesize into carbohydrates and fats
to make proteins. Any bean can. But before we can build
the protein of a bean or a peanut, or of milk or an egg or a
chop, into our own protoplasm, we must reduce these complex
substances to simpler ones. This building of protein into
our body is synthesis, but our synthetic power is far below
that of plants. We must first wreck a body that was alive to
get the material with which to build our own living body.
For example. We eat a mutton chop; we do not build a
mutton chop into our body. As mutton, it is of no value to
us; we can only use the materials mutton is made of. By the
time that chop is carted around by the blood and delivered
at cell doorsteps, it is no more mutton than a string-bean is
a fish. We make our own flesh out of the same materials
fish, beans, and sheep use in making their body. We recom-
bine these materials according to our own formulae. But we
can only recombine them when we have torn them down, re-
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THE PROCESSES OF LIVING AND THE GERMS OF DISEASE
duced them to materials the cells of our body know how to
use.
That is why we must digest food, that is what our digestive
system is for: to wreck the dead that it may be absorbed into
the living. Anything that can be absorbed is food. The
wrecking process is digestion, work; energy is consumed.
Food is also stored energy. But before that energy is avail-
able for us, we must reduce it to physiological fuel in our
alimentary canal.
5
A white blood-corpuscle swallows a bacterium whole. It
breaks it up into bits : digestion. Of these bits it selects such
as it requires: absorption. It opens its body and moves away
from such bits as it does not require: excretion. Simple
enough. Really, enormously complicated. Perhaps the most
complicated process known to man; and no man knows much
about it, even in phagocyte or ameba.
Each cell in our body is also a living animal and must
have its bits: building materials and energy for building and
for regulation. To prepare bits fit for cell requirements
is the special job of a special group of cells arranged in
special tissues and equipped for this particular purpose: the
alimentary canal and accessories, the digestive system. Its
sole business is to reduce dead matter to such standard sub-
stances as can be delivered by the blood and can be used by
living cells for vital processes. Any matter which can be thus
reduced and utilized by living organisms for vital processes
is food.
The alimentary canal is a single thirty-foot-long tube open
at both ends; most of it is coiled up in the abdomen. It is
lined with mucous membrane and coated with muscle which
contracts and relaxes, forcing food forward. These muscles
work ceaselessly under the drive of their own engines, of
which there are about 2,000,000 per inch of canal. Valves
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WHY WE BEHAVE LIKE HUMAN BEINGS
prevent food moving in the opposite direction. Below the
diaphragm the canal's outer muscle coat is serous, moistened
from the serum of lymph, as is also the mesentery or ruffled
peritoneal fold which connects the intestine with the back of
the abdominal wall. This makes them smooth and slippery;
they keep up their ceaseless movements and are not worn out
by friction.
Food is sampled in the mouth. If O.K.'d, it is chewed fine
and mixed with saliva, a secretion of the salivary glands.
This breaks it up, aerates it, moistens it, and makes it go
down easily: first step in reduction. That step signals the
stomach, "Get ready, food coming down"; the stomach be-
gins to secrete gastric juice.
From the mouth, food enters the cone-shaped pharynx
suspended from the skull — the busiest spot in the body at
meal times, especially if there is conversation. Its upper
mucous lining contains much lymphoid tissue. In that
children develop adenoids — best "outgrown" with a knife.
Adenoid growths may cause children to become "mouth
breathers," thereby opening the mouth to do the nose's work,
which is to prepare the air for the lungs.
Put your hand on your Adam's apple and swallow. Easy
as pie, but one of the most complicated processes in nature.
The esophagus must be opened, and passages to mouth, nose,
and windpipe must be closed. If the windpipe-man is asleep,
food starts for the lungs instead of the stomach. In the lungs
it is still out-of-doors, subject to any vulture that happens
along. We cough it up only when tlie windpipe cilia raise it
up within coughing distance. Fortunately, our swallowing
apparatus works so well that we do not often have to cough it
up. In fact, it is so complicated and does its work so well
that a swallowing center in the brain is assumed.
Once food reaches the esophagus or gullet, it is gone. The
mere act of swallowing suffices to shoot it to the upper or
sphincter end of the stomach. Time, one-tenth of a second.
If the food is semi-solid, it is forced down by peristaltic
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THE PROCESSES OF LIVING AND THE GERMS OF DISEASE
waves in the circular muscles of the esophagus. Time, six
seconds. Whether food is held up by the sphincter before
passing into the stomach proper (and if so, how long) is dis-
puted.
As ours is a mixed diet, we do not require such huge com-
pound stomachs as the hay-feeders have. Ours is a simple
stomach with a five-pint or six-hour capacity. That enables
us to give much time to other organs. Without a stomach,
we should have to nibble all the time.
Although simple, our stomach is not so well understood as
it might be. It has three muscle layers, lengthwise, oblique,
and circular. They vary in thickness in different regions,
and contract and expand according to the work they have to
perform. Thus, carbohydrates receive stomach treatment
different from that given to proteins and fats. But contrac-
tions begin a few minutes after food enters the stomach,
thereby further reducing it and mixing it with gastric juice,
which consists of mucin and pepsin. Pepsin is a combination
of hydrochloric acid and pepsinogen. All three juices are
secreted by glands.
As a result of mixture and contractions, the more liquid
food, called chyme, is forced toward the lower or pyloric
(gatekeeper) end of the stomach. The pylorus opens — so it
is believed — when the chyme pressing against it has reached
a certain degree of acidity. It now enters the twenty-foot-long
small intestine — the main seat of digestion and absorption,
the cleverest analytical chemical laboratory known to science.
Into this intestine a few inches from the stomach also come
bile from the liver and a fluid from the pancreas, also the
intestinal juice secreted by millions of tiny glands. Also,
now and then, the bacillus of typhoid fever or the ameba of
dysentery.
The lining or mucous coat of the small intestine is easily
one of the marvels of the world — in structure and accomplish-
ment. It is thrown into innumerable irregular but permanent
folds. These increase the surface of the mucous coat and
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WHY WE BEHAVE LIKE HUMAN BEINGS
slow up the passage of food. The surface itself is like velvet
or a bath-towel, due to four million minute finger-like pro-
jections, or villi. Each villus is connected with a lymph
vessel, an arteriole, and a vein; is inclosed in a layer of epi-
thelium; and contains a muscle. Under a microscope, each
villus can be seen to lash about and "pump" up and down.
Beyond is the large intestine (cecum, colon, rectum), from
five to six feet in length and from two and one-half to a half-
inch in diameter. Digestive and absorption processes are con-
cluded here. The cecum (blind) begins as a pouch, the
small intestine opening into it on the side. At the "blind"
end is the opening of the vermiform appendix, also blind,
also a threat, and of no known use to man except as a happy
hunting ground for gangrene and other bacteria.
Both small and large intestines have two muscle coats:
the outer, longitudinal; the inner, circular. They produce
two kinds of movements: peristaltic, or waves of constriction
which force food onward; rhythmic — local constrictions
which mass food in spots or areas and then break up the
masses. Such segregations. Cannon finds, occur every two
seconds. An animate churn, as it were; and "keep moving"
is its motto.
The two great organs of digestion are pancreas and liver,
both marvelous chemists. The pancreas secretes enzymes or
ferments; the liver works over materials brought by venous
blood from intestines, stomach, spleen, and pancreas. It
manufactures bile; turns glucose into glycogen; reconverts
glycogen into glucose when ordered ; and converts by-products
into urea. It is an enormously busy organ; the fires under
its retort are always burning; its blood requirements alone
account for one-fourth the entire volume of blood in the body,
or more than may be found in heart, lungs, and great blood
vessels at any given moment.
No heat, no digestion; digestion stops with ice water, re-
sumes when the blood has warmed the water to blood-heat.
If the blood gets chilled, it can find a warm spot in the liver.
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THE PROCESSES OF LIVING AND THE GERMS OF DISEASE
6
First on life's bill of fare is water. No water, no life.
A man of 150 pounds thoroughly dried out weighs 50 pounds;
he has evaporated that much water. Bones are nearly half
water; our blood, 90 per cent; the three-months' human
fetus, 94 per cent. And half the entire water content of
the body is found in muscles. Without water, no living proc-
ess takes place; nothing can take its place for washing away
our body's sins. Except for the early hunger pangs we can
starve to death in peace, burning our body for its energy,
dehydrating our tissue for its water. But without water and
on the desert we perish miserably within a few days, the
agony growing with the hours.
Other important inorganic foods are mineral salts: cal-
cium, iron, magnesium, chlorine, phosphorus, sulphur, so-
dium, potassium. They play important roles in vital proc-
esses and are found in all protoplasm. Silicon and flu-
orine are found in certain tissues and are presumably
necessary for our existence.
Iron in the protein of the red blood-cell carries oxygen.
Fluorine is a minor tooth-and-bone builder and possibly
helps form the cement which holds the cells together. Iodine
is found in the thyroid gland. Silicon is found in bones, hair,
and the crystalline lens of our eye. Chlorine is necessary
for the hydrochloric acid of gastric juice. Calcium and phos-
phorus are necessary for bone. There is no end to the im-
portance of these inorganic compounds or the uses the body
makes of them. Some are especially essential during growth.
They are found in the organic compounds of plant or animal
bodies which we eat as food; they are set free in digestion and
are available for growth and repair.
The three food groups proper are organic compounds:
carbohydrates, fats, proteins. We eat more carbohydrates
than fats or proteins, but they do not remain with us long:
137
WHY WE BEHAVE LIKE HUMAN BEINGS
we keep using them up day by day. They are the body's
primary sources of fuel.
Carbohydrates consist of sugars and starches and related
substances. Their chemistry is fairly simple, their structure
complex. To get an inkling of this structure is to begin to
understand several important biologic and physiologic phe-
nomena and will help explain why we cannot, for example,
digest sawdust, and why our liver must convert sugar to
starch or we die — without insulin.
Note, again, that carbon atoms alone can form such diverse
substances as lampblack and diamonds; the real difference
is in the way the carbon atoms are combined into molecules.
Carbon atoms are constituent elements of all carbohydrates;
the hydrogen and oxygen atoms present are always in the
proportions found in water. But with these water elements
the carbon enters to form structures not only of great com-
plexity, but (and this is the main point) of such structure
that the molecules cannot pass through the wall of the intes-
tine into the blood or can pass through the filter membrane of
the kidneys. In the one case the molecule never gets into cir-
culation, in the other it passes out of circulation before the
body cells can use it.
In other words, food is not what we eat, but what can be
so altered in the alimentary canal that it can pass through
the canal wall into the blood-stream and can be used by the
body mechanism for building, fuel, or storage purposes. Most
foods are insoluble colloids or colloidal in nature: during di-
gestion they are converted into soluble crystalloids; as such
they can pass into the blood-stream; as colloids they cannot.
By rough analogy, diamonds are crystalloid, lampblack is
colloidal. If our digestive laboratory could wreck the crystal-
loid structure of a diamond molecule so that the carbon
atoms could pass into our blood-stream, we could be said to
digest diamonds. It cannot use the carbon atoms in a dia-
mond because it cannot wreck the diamond molecule. The
138
THE PROCESSES OF LIVING AND THE GERMS OF DISEASE
same clay-pit may furnish the mud for a hovel and the brick
for a Michigan Avenue French chateau.
We tap a maple tree and collect the sap; boil it down to
sugar, which crystallizes and is soluble. We eat the sugar;
reduced further in the alimentary canal, it passes into the
blood-stream and is converted in the liver to glycogen (animal
starch), colloidal, insoluble; it can now be stored, in muscle,
for example. The sap flows up the tree, the tree converts it
into cellulose and other complex starches; for the tree, the
sugar is immediate or reserve food and cellulose.
There is almost no end to the specific carbohydrates in the
plant world. Of these, some twenty important kinds are
recognized and are divided into three groups.
The monosaccharides, glucoses, or simple sugars, generally
contain six atoms of carbon (the hexoses) ; a few, only five
(the pentoses). Glucose, dextrose, or "grape-sugar," is
found in all animal tissues and in all fruit juices. Commer-
cial glucose is manufactured from starch. Fructose, or
"fruit-sugar," is found in honey and many plant juices.
Galactose is found in such combinations as the cerebrosides
of the brain and in vegetable gums. Arabinose is found in
gum-arabic and cherry-tree gum.
The disaccharides, or complex sugars, are formed by the
combination of two monosaccharide molecules, with the elimi-
nation of a water molecule. The three important complex
sugars are: sucrose or cane-sugar, in sweet juices of plants,
especially in sugar-cane, sorghum cane, sugar maple, and
sugar beet; lactose or milk-sugar, in milk; and maltose or
malt-sugar, in malted grains.
The polysaccharides are still more complex. They are
formed of monosaccharides by combining variable numbers
of sugar molecules and eliminating a corresponding number
of water molecules. The formula of some polysaccharides
is so complex as thus far to baffle analysis. Starch, found in
grains, tubers, roots, etc., as stored energy for growth, occurs
in two forms, but whether the difference is chemical or merely
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WHY WE BEHAVE LIKE HUMAN BEINGS
physical, and whether there are one or many kinds of starch,
is not known. But every kind of plant has its own distinctive
starch grain — otherwise we should not know whether our
"tapioca" is sago or mere potato. The starch grain of a bean
is as unlike the starch grain of corn as a grain of corn is
unlike a bean. Three-fourths of the potato and more than
half of cereals is starch. Sago, tapioca, and arrowroot are
almost pure starch.
Other "starches" are glycogen, found in all animal tissues
and in yeast; agar-agar, found in seaweeds; lichenin, found
in Iceland moss; gum-arabic, found in certain trees; and
cellulose.
Cellulose forms the cell-wall of plants, the hard part, the
fiber; cotton, linen, straw, wood. Celery, beets, and turnips
contain more cellulose than fruits, potatoes, or flour. What
bone is to animals, cellulose is to plants. That is why we
cannot digest it and why trees are possible. If we could digest
it, sugar would be as cheap as sawdust. Herbivorous animals
can utilize it because they have a large cecum where cellulose
can be retained for a long enough time to be fermented by
bacteria. Our cecum is relatively smaller and does not retain
food so long; the cellulose we ingest is excreted.
Yet chemically, cellulose is potential sugar. Why, then, the
peculiar qualities of wood, and why can we not digest saw-
dust? Because, as Sponsler has recently shown, of its peculiar
architecture. We cannot wreck it. The atoms in a cellulose
molecule are arranged on an up-and-down plan like beads on
a string, and the beads cling together for dear life. In an
inch-long piece of match there are many strings of "beads";
each string or column contains about 50,000,000 molecules
end to end. They are pulled apart only with great difficulty.
Wood is more easily split lengthwise than broken across,
more easily crushed lengthwise than pulled asunder, swells
sidewise but not lengthwise, and is digested by no animal
higher than protozoa. Even termites or "white ants" can-
not eat up furniture and houses without the assistance of the
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THE PROCESSES OF LIVING AND THE GERMS OF DISEASE
microorganisms which infest their alimentary canal ; deprived
of their parasitic digesters, they starve to death within a
month.
The second great group of organic foods is fats; "compara-
tively inert substances with long, complicated formulae," Du
Bois characterizes them. They consist of one molecule of
glycerin (an alcohol) and three of a fatty acid: palmitic,
stearic, oleic, etc. Oleic acid is found in vegetable oils: olive,
peanut, corn, etc. In process of digestion such foods — under
the body's own steam, water, enzymes, and mineral acids —
are reduced to glycerin and fatty acids. Outside the body,
they are reduced to glycerin and soap. The late World War
fat shortage was due to the wholesale wreckage of fats to
recover the glycerin to make into nitroglycerin.
Lipoids are complex fats, so complex that their chemistry
is not well understood. One group contain phosphorus and
are thought to occur in every living cell, especially in nerve
tissues. Lipoids are found also in the liver, muscles, and yolk
of eggs.
Bulk for bulk, no food contains so much potential energy
as solid fats and oils. When eaten, fat can be burned or
stored. The Eskimo eat it to keep warm. Whales wrap a
foot-thick layer around their bodies for the same purpose —
fat is a great insulator. Certain Ungulates have special fat
reservoirs for lean days: the humps of camels and drome-
daries and of the humped or sacred cattle of India, and the
tails of fat-tailed sheep.
Proteins are complex beyond end. For example, a mole-
cule of cane-sugar has a molecular weight of 342; of hemo-
globin, 16,669. But that gives little suggestion of their
dissimilar organization. It is like comparing a grain of
sugar with an egg.
Protein, freed of all else, is colorless, tasteless, odorless;
and the basis of every cell in life from bacterium and alga
to giant redwood and man. Apart from water, protein is the
big constituent of eggs, cereals, peas, beans, lentils, peanuts,
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WHY WE BEHAVE LIKE HUMAN BEINGS
fish, flesh, and meat. The building-blocks of proteins are
amino acids, organic compounds in which one hydrogen atom
is replaced by a chemical compound closely related to
ammonia.
Twenty different amino acids are known. Most of these
have been discovered in the protein of milk, wheat, corn,
gelatin, chicken, and beef. But foods vary in the number
of their amino acids and the relative amounts of each. The
possibilities in their combinations are staggering, chemically
practically infinite. There is milk and milk, and flesh and
flesh, and eggs and eggs : each of its own kind. Just as mutton
fat built into the human body becomes quite a different kind
of fat, so with protein. From the legumin of beans or the al-
bumen of the white of an egg, or the gluten of wheat, or the
gelatin of an ox's tendon, man builds his own protein struc-
ture.
But we could not do it without vitamins. Until recently no
one had ever seen a vitamin, nor had the chemical labora-
tory isolated one ; sixteen years ago no one had ever heard of
one. And yet a real science of food is impossible without a
knowledge of vitamins. Without vitamins (or something just
as good) there is no normal growth, health, reproduction, or
living out the span of life.
Scurvy was known to the ancient Greeks, and through the
centuries ravaged armies, crews of ships, and explorers cut
off from fresh fruit and vegetables; seven years ago no one
suspected the existence of the antiscorbutic vitamin. Thou-
sands of children have hobbled out a pitiable existence on a
rickety frame; until recently no one suspected it was because
of lack of a specific mysterious antirachitic vitamin now
known to exist in certain foods. About thirty years ago it
was known that chickens fed on polished rice developed beri-
beri, and that the same chickens fed on whole rice recovered;
but no one then suspected the existence of an antineuritic
vitamin in the polishings of rice or in milk.
Innumerable experiments have now proved the existence of
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THE PROCESSES OF LIVING AND THE GERMS OF DISEASE
four, and possibly five, vitamins, and their necessity for
human life and the metabolism of all food. Because of their
minute amounts, their close association with the complex food
substances, their proneness to disappear under manipulation,
and because no good controls could be devised in testing, they
defied isolation. But, by relying on feeding and by huge
industry and patience, definite results have been obtained —
and civilization again catches up with desiccated and tin-
canned progress. In other words, the human body could
find all it needed in the old vegetable garden and shambles;
when food began to be refined, the vitamins were thrown out
with the screenings.
Fat-soluble A (because soluble in fat), or antirachitic
vitamin, is probably first in importance. All animals experi-
mentally treated die if their diet contains no vitamin A. It
is presumably necessary for all higher animal life. It is
known to be necessary for growth. Rachitic children pre-
sumably suff'er from lack, among other things, of vitamin A.
With vitamin A their bones assume normal growth. Rachitic
children were numerous in parts of Europe during the World
War; when the milk supply became normal, the rickets
disappeared.
Vitamin A abounds in milk, cream, butter, egg yolk, cod-
liver oil, and presumably all animal fat except pork. It is
less abundant in spinach, tomatoes, cabbage, and lettuce. It
is not destroyed by ordinary cooking, but is destroyed by great
heat.
According to a recent announcement, a semi-crystalline
product containing carbon, hydrogen, and oxygen has lately
been isolated by Takahashi and Kawakami from cod-liver
oil, butter, and egg yolk. Presumably it is vitamin A in
nearly pure form. Mice nearly dead from lack of fat-soluble
A have been completely restored to health by small doses
of the substance.
Water-soluble B, or antineuritic vitamin, is found in eggs
and seeds. It is essential to growth, and lack of it is known
143
WHY WE BEHAVE LIKE HUMAN BEINGS
to produce beri-beri. Seidell has recently isolated in nearly
pure form from brewers' yeast a substance which has anti-
neuritic properties. Presumably it is vitamin B.
Water-soluble C, or antiscorbutic vitamin, has thus far de-
fied isolation in any form. It is easily destroyed by alkalies
and by oxidation. It is found especially in lemons, oranges,
and tomatoes; also in all fruits, leaves, and root vegetables.
Without such foods, scurvy. In the World War Mesopotam-
ian campaign, Indian troops suffered from scurvy, British
troops from beri-beri. The Indians were living on dried beans
and peas, the British on tinned beef and biscuit. The dried
beans and peas had lost their antiscorbutic vitamin, the white
flour its antiberi-beri vitamin.
Vitamin D, known to accelerate growth, is probably iden-
tical with bios, a substance that promotes the growth of the
yeast plant. Its molecule consists of five atoms of carbon,
eleven of hydrogen, one of nitrogen, and three of oxygen.
Enough bios to cover a pin-point will restore normal growth
in a young animal stunted by a diet which does not have
proper vitamins.
Vitamin X is the latest. Evans has been experimenting
with rats. If they get no vitamin X, they become sterile. He
has also proved that natural foods contain a substance or
substances essential for the normal functioning of the mam-
mary gland. But certain substances (for example, vegetable
oils) which promote fecundity do not necessarily improve
lactation.
In short, there are foods and foods: water, mineral salts,
carbohydrates, fats, proteins, vitamins. Is sunlight a "food"
also? It depends. Children and hogs that play in the sun
need no antirachitic vitamin; they do not develop rickets.
Light is a marvelous oxidizing agent. Foods with no known
vitamin A can by ultra-violet radiation become possessed of
antirachitic property. These same rays get into our skin and
"sunburn" us; they will paralyze an ameba in a quarter of a
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THE PROCESSES OF LIVING AND THE GERMS OF DISEASE
second, or kill and tear its body asunder like a bolt of light-
ning in three seconds.
How much of this or how much of that is good or necessary
or lethal for us is a kind of knowledge that did not seriously
trouble our remote ancestors, but which, with our increasing
tendency to get away from cows, chickens, and gardens, and
from natural conditions in general, becomes of first-rate im-
portance. There was a time when a cook was a cook, good
or bad as the case might be; to-day a cook should be a first-
class chemist, the kitchen a chemical laboratory.
Meanwhile, before we journey through the canal with food,
it will be well to recall a fact of great importance. We eat
food — and should enjoy it; it is the individual, microscopi-
cally small cells of our body that are the ultimate consumers
of that food. If these cells cannot use it (oxidize it for its
working energy, or build it into themselves in repair and
growth), we may have enjoyed our meal, but our body is as
unnourished as though we had fasted and is poorer by
the amount of energy expended in passing it through the
mill. It is one thing for us to eat food and for our digestive
system to analyze it; it is quite another matter (possibly the
least understood phenomenon of living beings) for the cells
of our body to synthesize it. Their astounding capacity to
find what they want in astonishingly dilute solutions!
With one part of carbon dioxide in 6,000,000 of water, an
alga can grow. An ameba can find enough nitrogen in a
solution which contains one part nitrate per million of water.
Formaldehyde, if it exceeds one part in a thousand, is poison
for an alga, yet when the solution of formaldehyde is less
than lethal it will synthesize sugar, if deprived of carbon
dioxide, from the vapor of formaldehyde. These figures,
from McCollum, help us to realize that our digestive system
must not only so reduce complex molecules that they lose their
original structure, but that the resultant substances must be
furnished to the cells of the body in proper solutions and
"at a favorable rate."
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WHY WE BEHAVE LIKE HUMAN BEINGS
7
The mechanics of digestion is simple. Food is chewed
and swallowed. Esophagus drives it to the stomach. Stomach
kneads it. Intestines roll it over and around and about,
thoroughly mixing it with the juices of digestion.
The chemistry of digestion is the removal of one or more
molecules of water (hydrolysis) through the operation of
enzymes. Thus, foods are so reduced that the substances of
which they are composed can be absorbed by the tissues of
the body or used for fuel to make heat or energy.
In these processes, carbohydrates are reduced to "simple
sugars"; fats, to glycerin and fatty acids; proteins, to amino
acids. These are purely chemical processes. The alimentary
canal is the chemical laboratory where these processes take
place; especially the small intestine. In chemical labora-
tories outside the body, such processes take place only with
high temperature and catalyzers (dissolvers) .
Catalysts are curious in this: they hurry the reaction, are
themselves unaltered by it, and to that extent do not actually
take part in it. Thus, phosphorus will burn in oxygen in the
presence of water, the water is unchanged ; without the water,
the phosphorus will not burn. The water was a catalyzer.
Again, cane-sugar (sucrose) hydrolyzed with hydrochloric
acid is reduced to glucose and fructose; at the end of the
reaction there is as much hydrochloric acid as there was
before, unchanged, as good as new, ready to do the same thing
again when called upon. But as it passes on into the intestine
with food it must be absorbed — presumably as something
else — and again put into the stomach through the secretion
of glands. Sucrose can also be reduced to glucose and
fructose in boiling water, but it is a slow process. The cata-
lyzer (hydrochloric acid) speeded the reaction, as will any
acid that has electrically charged hydrogen ions. All carbo-
hydrates, fats, and proteins can be hydrolyzed with great heat,
or with catalysts.
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THE PROCESSES OF LIVING AND THE GERMS OF DISEASE
During hydrolysis, whether by boiling or with a catalyst,
the compound loses one or more of its molecules of water.
The polysaccharides hydrolyze into several and the disaccha-
rides into two monosaccharide molecules.
Our body temperature is so regulated as to remain con-
stant at about 99 degrees. We cannot boil foods in our body
laboratory. The body prepares its own catalysts: enzymes,
chemical reagents that preside over every chemical reaction
in living organisms.
Enzyme means "in-leaven"; because, like yeast, it causes
fermentation. But yeasts are unicellular plants and make
their own enzyme, zymase; with that as catalyst, they ferment
sugar to alcohol, carbon dioxide, etc.
No one has yet seen or isolated an enzyme; perhaps no one
ever will. It is said that ultra-violet light rays of suitable
length will bring about all the reactions which can be pro-
duced by catalyzers; but that gives us no light at all on how
enzymes perform in living bodies.
An acid or an alkali reagent splitting a complex molecule
has been compared to a hammer which smashes a clock and
then picks out the undamaged particles. But enzymes, says
Bechold, are more delicate tools: they are like keys which
may unlock a thousand locks and fail when worn out.
Armstrong thinks it possible that enzymes do not exist as
entities: that they are part of a larger colloid complex; and
that enzyme action is an interaction in which water is either
distributed upon a single molecule which is thereby resolved
into two others, or divided between two molecules, so that
one is hydroxylated and the other is hydrogenated. In the
strict sense of the term, then, an enzyme is not an entity, al-
though it may have a double function: it attracts the hydrolyte,
it determines its hydrolysis — it is both acceptor and agent,
Armstrong suggests that synthesis in living cells is also
brought about by enzyme action. Possibly all metabolic
activity within or between the cells of the body may be due to
enzyme action. In other words, the enzyme can not only
147
WHY WE BEHAVE LIKE HUMAN BEINGS
smash the clock but can make one, provided it has the
materials.
Enzymes are relatively unstable and limited in their action,
specifically selective and mainly hydrolytic. They activate
water molecules. Hence it is assumed that they are struc-
turally related to the substances (substrates) on which they
act. It is their selective activity which forms the mechanism
of metabolic regulations; otherwise katabolic or destructive
changes would be uncontrolled. "Once the enzyme complex
is formed, an electrochemical current in which active water
molecules take part is completed; the energy being supplied
. . . disruptive changes take place, leaving the enzyme free
to form a fresh complex."
Reference has been made to the storage of sugars and fats
in roots and seeds of plants. Something happens to these
stored foods when the roots or seeds begin to sprout or germi-
nate. The change that then takes place is due to enzyme ac-
tion. A potato, for example, in a dry, cool cellar, breathes
— absorbs oxygen, gives off carbon dioxide. Its enzymes
are quiet. But suppose that the potato is frozen ; its enzymes
become active. Its amylase digests its starch to sugar, it
becomes sweel; its protease reduces its proteins to amino-
acids, it becomes bitter. But freezing has killed its germ:
it is a dead potato; it can no longer defend itself against
bacteria and, as McCollum says, soon rots.
It is presumed that the enzymes in the potato were in an
inactive state. Freezing activated them. During freezing, a
crystalloid was added to the colloid complex enzyme — it
became "activated." Such an activator of an enzyme is a
zymogen.
Pepsin, for example, is active in the alimentary canal only
when activated by hydrochloric acid. The zymogen of pepsin
is pepsinogen. Again, oxidases make biologic oxidations
possible pre sumably by forming a system of organic sub-
stances which can lake up molecular oxygen to form peroxide
148
THE PROCESSES OF LIVING AND THE GERMS OF DISEASE
and part with one or both atoms to another substance, the
transfer being hastened by a zymogen, peroxidase.
The enzymes in the potato in the cellar were inactive,
inhibited. They are destroyed at the temperature of boiling
v,^ater — the boiled potato is still starch and protein. All
enzymes act best at certain temperatures. The enzymes of
our body find such optimum temperature because of the
capacity of the blood to maintain a temperature at which they
Yvork best. Enzymes are also governed by their hydrogen ion
concentration. Enzymes that have an optimum reaction in an
acid solution will become less active, or active not at all, in
an alkaline solution. The mouth juices are alkaline, the
gastric juices acid; we shall not expect to find the same
enzymes in the mouf.h that we do in the stomach.
Howell divides enzymes into the following seven groups:
proteolytic or protein-splitting; amylolytic or starch-splitting;
lipolytic or fat-splitting; sugar-splitting; coagulating (rennin,
for example, which coagulates a soluble to an insoluble pro-
tein); oxidizing, or oxidases; and deaminizing — whereby
amonia, for example, is split from alanin, which is thereby
reduced to lactic acid.
The first four groups are the important digestive enzymes.
But they are not confined to the alimentary canal. Presum-
ably both fat-and sugar-splitting enzymes are present in the
blood and other tissues, especially muscle.
The fact that many enzymes exist in an inactive or zymogen
stage both in secreting cells and after secretion and require
activating before they function, suggests another interesting
and important biologic phenomenon: the capacity of the blood
and other tissues to form dissolvers or antibodies to foreign
protein substances. We shall have a look at these antibodies
presently; we now resume our voyage through the alimentary
canal.
During digestion, food is mechanically reduced to particles
that can be carried in the watery fluid of the canal. In the
canal, it is mauled about and churned up with the agents and
149
WHY WE BEHAVE LIKE HUMAN BEINGS
reagents of chemical action. It is always meeting new phy-
sical and chemical conditions. In the mouth food is mixed
with saliva, of which we secrete from one to two quarts a
day. It contains two enzymes (ptyalin changes starch to
dextrin and maltose, maltase changes maltose to glucose) and
mucin, a lubricator.
Saliva is slightly alkaline; the gastric juice of the stomach
is strongly acid and contains three enzymes: pepsin, splits
proteins; rennin, coagulates milk and converts casein to
paracasein; lipase, splits fats in emulsion, such as cream.
The stomach, then, is the important digester of proteins,
especially meat, flesh, fowl, fish, eggs, and milk. How the
stomach can secrete a free acid such as hydrochloric from
blood which is a neutral fluid, is as yet an unsolved mystery.
It does. That acid is a fine antiseptic or disinfectant and
checks bacterial growth, except that which causes acid fer-
mentation. But too much acid makes for hyperacidity : gas-
tritis, gastric ulcers. The flow of gastric juice is inhibited
by emotional stress and pain, by anything which rouses the
sympathetic nervous system to activity.
When food reaches the intestine it has lost its looks and
much of its nature — digestion begins in the mouth. In the
intestine it loses everything it was as food for eye or mouth,
to become something that a cell can use or spend. It meets
with about a pint and a half of pancreatic juice: very alka-
line, rather sticky, and charged with three enzymes: trypsin,
leaves the pancreas as trypsinogen (a zymogen) and becomes
trypsin in the small intestine; it is a proteoclast, breaks down
proteins into their constituent animo-acids; amylase, acts like
ptyalin, hydrolyzing starch to maltose; and lipase or steap-
sin, which hydrolyzes or saponifies fats into glycerin and
their constituent fatty acids. Lipase is also found in the
mammary glands, muscles, liver, blood, etc. It seems that it
also acts as enzyme in the synthetic processes involved in
reconverting the glycerin and fatty acids of lard, butter,
150
THE PROCESSES OF LIVING AND THE GERMS OF DISEASE
cream, oil, etc., into the kind of fat we store in our adipose
tissue.
Food in the small intestine also meets a secretion of the
glands of the intestine, the succus entericus. That intestinal
juice contains six enzymes: enterokinase, a zymogen which
converts trypsinogen to trypsin; erepsin, completes any
unfinished business of trypsin and pepsin; nuclease, acts on
the nucleic acids of the nucleoproteins ; maltase, converts the
maltose and dextrin of starches to dextrose; invertase, con-
verts cane-sugar to dextrose and levulose; lactase, converts
milk-sugar to dextrose and galactose.
Secretin is also an assumed constituent of intestinal juice.
Its chemical nature is not known. It is probably not an
enzyme. It seems to act as a messenger. Carried to the
pancreas, it stimulates that gland to send its juice to the
intestine.
Food in the small intestine also meets the bile, a constant
secretion of the liver, stored in the gall-bladder, and deliv-
ered periodically to the intestine when needed. Bile is a
thick, bitter, alkaline liquid. Its color, varying from golden
yellow to dark olive green, is due to iron pigments from
broken-down red blood-cells. Some of these pigments are
returned to the liver via the portal vein; some are eliminated
by the alimentary canal and color the excreta. Bile pigment
which gets into the skin colors it yellow and is called jaun-
dice, but is not infectional jaundice.
Bile also carries two acids or "salts," secretions of the
liver cells. Their function is not definitely known. They
are partly returned from the intestine to the liver and pre-
sumably stimulate the liver to further activity. They prob-
ably assist in turning fat into soap in the small intestine and
so make its absorption possible. They apparently help dis-
solve cholesterol.
Cholesterol, a "solid alcohol," is ingested with food, but,
as shown by Gall, can be synthesized by the liver. It occurs
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WHY WE BEHAVE LIKE HUMAN BEINGS
in every cell of our body, especially in nerve cells; it is
found in the secretions of the fat or oil glands of the skin
(in sheep's wool also, and, when extracted, called lanolin) ;
it is found in blood, milk, yolk of egg, kidneys, and adrenal
glands. It stimulates growth of cancer. When it crystallizes
in the human gall-bladder, it is called cholelith (gallstone) ;
when in the sperm whale, ambergris. Wliy gallstones, and
all that cholesterol is or does, are not well known; this is
partly due to its stubborn resistance to biological and chem-
ical reactions.
"Synthesized by the liver" — I should have said "liver
cell." Of which there are many many millions, for the liver
is the largest gland in the body. Each liver cell is an
"organ." In each cell (according to Bechold) are 225,000
million water molecules, 2,900 million crystalloid molecules,
166 million fat molecules, and 53 million protein molecules;
and each molecule bafflingly complex beyond power of
description! That cell is more than a mere cell; it is a busy
little world. No wonder that a liver which has to handle
copper from worm-stills or copper vessels for twenty years
gets discouraged and catches atrophic cirrhosis. The human
liver is organized to deal with iron, sugar, etc., but not with
copper. Presumably this copper hastens the break-up of red-
blood cells. Too much pigment in the liver. The cells
sicken and die.
All in all, a normal adult pours about five quarts of
digestive juices into his intestine each day. About four and
one-half quarts of these juices are reabsorbed and presum-
ably worked over again for secretion by the various glands
of digestion.
Why does not the intestine digest itself? Or tapeworms — •
they are in the presence of trypsin, a powerful enzyme? But
juice of a dead tapeworm mixed with juice of the pancreas
stops trypsin action. It seems as though the tapeworm has a
substance which inhibits the action of trypsin; with that it
152
THE PROCESSES OF LIVING AND THE GERMS OF DISEASE
saves itself from being digested. Otherwise it could not stop
the action of the enzyme.
The alimentary canal does not digest itself because it is
protected by the slimy coat of mucus secreted by its living
lining cells. But when there is nothing in the canal for the
secretions to work on and the pancreas is artificially stimu-
lated to discharge its secretion into the canal, an irritation
is set up as though brought about by digestion.
Food begins to enter the large intestine about two hours
after it passes the mouth, but not until about ten hours later
has the last of the meal left the small intestine. The secretion
of the large intestine is alkaline, contains mucin, but no
enzymes. The digestive enzymes from the small intestine
continue if there is any unfinished business. The time
required for food to make the entire canal journey is from
twenty-four to thirty-six hours.
The chief digestive change in the large intestine is prob-
ably due to bacteria, the "intestinal flora." These multiply
so rapidly that about half the contents of the lower part of
the large intestine are bacteria, excreted at the rate of about
130,000,000,000,000 a day. They are of no knoiun positive
benefit. They may act on otherwise indigestible cellulose;
they may synthesize proteins from ammonium salts in such
form that the protein can be absorbed; in which case they
should not be outlawed, because bacteria are cheaper than
enzymes.
The small intestine also has its bacterial colonies which
are responsible for ammonia and at least five kinds of intes-
tinal gases. Their action is chemically not unlike that of
enzymes; but whether bacteria are positively harmful in our
alimentary canal is as yet a moot and unsettled problem. As
the stomach is sterilized by the gastric juice, bacteria do not
grow there and it is comparatively free of bacteria. But
they may escape the action of hydrochloric acid inside solids
or undigested particles, and so pass on into the small intes-
tine, where they can grow. Bacteria are sometimes found in
153
WHY WE BEHAVE LIKE HUMAN BEINGS
hens' eggs; they got in during the hours the egg was in
transit from the ovary and before the shell was formed.
8
Digested food in the alimentary canal is as useful to the
body as when in the butcher shop or grocery store. It must
pass from the canal into the blood before the body can eat
it. This is called absorption.
What is absorbed? What is a "square meal" when
digested? Sugars and starches have become "simple"
sugars; fats have become glycerin and fatty acids. Huge
protein molecules of from 12,000 to 15,000 weight and con-
sisting of a hundred or more amino-acid molecules linked
together, have been dehydrolyzed into their eighteen to
twenty constituent amino-acids and certain mineral salts. One
of these salts may be silicon — invaluable for glass eyes and
all glass; absorbed within the blood and carried to the eye,
it is built into the crystalline lens. Only the diamond is
harder than silicon. We cannot eat silicon; our digester
finds it in milk and bamboo shoots.
Alcohol, pepper, mustard, etc., are absorbed in the
stomach; especially alcohol, and so readily that little of it
reaches the small intestine. Water is not absorbed in the
stomach, nor to any great extent in the small intestine ; chiefly
from the large intestine.
The small intestine, with its sixteen square feet of absorb-
ing surface, is the great absorber, as it is the great digester,
of food. During absorption, the sugars and amino-acids
pass from intestine to the capillaries in its walls and are
then passed into general circulation? Not at all; they are
carried by the portal vein to the great pool in the blood
stream, the liver. We shall see why presently. During
absorption, soaps, fatty acids, and glycerol are resorbed and
are carried away as chyle to the lacteals of the lymphatic
system and so into general circulation via the lungs. It is
154
THE PROCESSES OF LIVING AND THE GERMS OF DISEASE
this neutral or "emulsified" fat that gives chyle its milky
look, hence the lymphatics of the intestine are called
lacteals.
But how? The intestine is not a tube of blotting paper
or of charcoal; its surface is a solid wall of living cells.
How do these lifeless building-blocks get through that wall?
Over a salt solution in a bowl place a layer of pure water.
Salt molecules enter the top layer. This is diffusion. Water
and oil do not mix; such a liquid is indiffusible.
On one side of a membrane in a bowl place a salt solution;
on the other side, pure water. Water molecules will enter
the salt solution. This is osmosis: the less dense solution
(water) will pass toward the stronger solution. Osmotic
pressure lifts water from the soil to the top of the highest
tree.
On one side of the membrane place a solution of white
of egg and salt; on the other side, water. Salt will leave
the egg and enter the water until the concentration of salt
on each side is equal. This is dialysis.
These three laws of physics help us to understand what
goes on during absorption. But there are difficulties.
Why did the salt only leave the egg, why did not the egg
also pass through the membrane? Egg is colloidal. Its
molecules are too large to diffuse through membranes.
Inorganic salts are diffusible: they are crystalloids; their
molecules are relatively small. Digestion is largely a process
of breaking large molecules into their constituent relatively
small molecules.
It is one thing to know that a certain organic compound
building-block called an amino-acid is set free in the process
of digestion; it is quite another question how this block gets
through that wall of live cells. And still another question —
and one of life's deep secrets — ^how this or that cell builds
that block into its own structure and at the same time stamps
it with its seal of individuality so that it is now unique both
for the species and for the kind of tissue it is in. What was
155
WHY WE BEHAVE LIKE HUMAN BEINGS
a non-specific simple compound has now been synthesized
by the cell into its own complicated specific self. When
we learn how the cell does that, we may hope to build a
living cell.
Consider that the sugars, amino-acids, and fatty acids have
passed that wall of living ceils, v/hat then? Much is known.
The sugar or glucose is stored by the liver as glycogen.
Why stored, why glycogen? Sugar is crystalline, soluble;
if left in the blood, it would be washed out in the urine;
glycogen is colloidal, insoluble. As a result of this storage,
the blood sugar concentration may remain normal at one
part in a thousand. When the body needs fuel, the liver
reconverts glycogen to sugar and sends it out into the blood.
Small amounts of glycogen are also stored in the muscles
and all active tissues. Excess sugars are synthesized into
fat.
The fats are carried about by the blood and taken up by
the tissues that need fuel; oxidized, they supply energy.
Wlien thus burned, the "ashes" are carbon dioxide and water.
All fat not required is stored: adipose tissue. Fat. People
get fat because they eat more sugars and fats than they use —
and unless they contemplate fasting or fear starvation, they
carry a senseless and an unnatural burden.
For biologic oxidations, fats are relatively the most impor-
tant foods. One pound of fat has a fuel value equal to two
and one-quarter pounds of carbohydrates or proteins.
No body is built, or kept alive and warm, without energy.
The body requires enough energy: to keep alive (depending
on age and other factors) and to run the digestive system
(often called "cost of digestion") ; to work; to keep in repair.
Say 2,500 calories for a man of 170 pounds. Of these
calories, from 10 to 15 per cent should be in proteins. If
one does manual work, or loves to store fat, the calories may
be increased up to 10,000.
The sugars are carried to the liver first; so are the amino-
acids, the raw material from which the body builds itself,
156
THE PROCESSES OF LIVING AND THE GERMS OF DISEASE
with which it keeps itself in repair. "Repair" is not to be
thought of merely as new tissue to heal a wound or new
protoplasm to replace that being constantly shed by nails,
hair, and the epidermis of the skin. There must be the raw
materials for the building of new blood-cells, for glandular
action, for hormones and enzymes, and for the eternal wear
and tear of heart, nerve tissues, and all the organs which
function ceaselessly until chilled in death. The blood is
their environment. From the blood they must obtain such
amino-acids as they require, when they require, and in proper
solution. Too great concentration is fatal to certain tissues,
fatal to heartbeat; too great concentration of the end-product
of their metabolism, ammonia, is likewise fatal. The kidneys
play their part, but they can be damaged by too much of
the digested products as well as by too much of the end-
products of metabolism. It is because the liver receives
the amino-acids direct from the small intestine that they pass
into general circulation slowly and in proper concentration.
When the liver functions badly from disease, the amino-acids
are fed into general circulation faster than the tissues can
use them up; they escape in abnormal amounts through the
kidneys. While amino-acids have no "threshold value" for
the kidney filter, we lose little if they enter the blood-stream
slowly.
In the blood-stream, the amino-acids are carried about
for the use of such tissues as require them. What is not
required is normally broken down in the liver — "deamin-
ized." The non-nitrogenous element is then useful for fuel
and may be converted by the liver into glycogen and stored.
The nitrogenous element, ammonia, is turned into urea and
handed over to the kidneys for elimination.
When the body eliminates as much nitrogen as it receives
in the form of protein nitrogen, the body is in "nitrogen
equilibrium": it is not burning flesh, but fuel. If the bal-
ance is in favor of intake, the body is growing: "taking on"
157
WHY WE BEHAVE LIKE HUMAN BEINGS
flesh. Flesh is not fat, although it can be burned as fat, as it
is during starvation.
Why so much bother? Why not eat glucose, glycerin,
soap, and amino-acids, and save wear and tear of teeth, action
of thirty feet of canal, and secretions of countless glands?
Why not predigested food? Sounds reasonable. But try it.
Try a meal of amino-acids. Even a rat will starve to death
rather than eat a mixture of amino-acids. They are about
as unpalatable as anything could be; in milk, ham and eggs,
string beans, lamb chops, and the innumerable forms in
which we ingest amino-acids, they are palatable.
Even pure sugar as the sole source of carbohydrates would
soon sicken us — nor could we taste anything else. Starches —
in dozens of forms — are in themselves tasteless, but carry
odors and flavors which make them appetizing. And as for
a diet of fatty acids and soaps! Good butter is good, but
its butyric, caproic, caprylic, and capric acids taste bad and
smell worse.
Further, foods in concentrated crystalloidal form would
irritate the mucous lining of the canal and cause the blood
to give up its salts to the canal. A bacterium cannot digest
salt or sugar; salt or sugar can "digest" a bacterium, absorb
its juices; but a bacterium can live in a weak solution of
sugar or salt.
In short, as McGollum (from whom I have drawn freely)
says, it is neither possible nor desirable to nourish the body
with predigested foods. But when it becomes necessary to
resort to rectal feeding, predigested foods are necessary;
otherwise they could not be absorbed, because the large
intestine is little concerned in digestive processes.
Life is protoplasm. Protoplasm is a solution — mostly
water. Water comes before and after food in life. In all,
from eight to ten glasses a day or the equivalent in water-
laden food. If alcohol is consumed, less water is required;
the end-products of an alcohol "jag" are carbon dioxide and
water. This brings us back to the blood again.
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THE PROCESSES OF LIVING AND THE GERMS OF DISEASE
9
There are more things in the blood than were dreamt of
in Horatio's philosophy or Moses could have imagined when
he said that "the life of the flesh is in the blood." Had
blood been better understood in 1799, Washington would not
have been bled to death to cure him.
While it is important that we do not lose sight of the
individuality of the body or of the organism as a whole, and
the fact that parts, organs, even cells, as parts, organs, or
cells, are meaningless, it is equally important to remember
that the body is made up of cells. These cells have sur-
rendered certain functions to groups of cells, tissues, and
organs, but they are the ultimate living units of the living
body; they must get their face next to food, air, and water,
and have their garbage removed. The blood performs this
service. The blood is their physical and chemical environ-
ment. It is an integrating organ to the extent that it keeps
the cells at a proper temperature and furnishes them with the
proper hydrogen ion concentration, the right kind of mineral
salts, sufficient oxygen and fuel for energy requirements, and
the proper amounts of brick and mortar for growth and
repair. A single-celled organism has such matters in its own
hands, but the cells in our body depend on the blood. The
blood is their world; without the blood they are as hope-
lessly isolated from life-yielding energies as would be a
child on a cake of ice in an antarctic sea. The blood itself,
without arteries, veins, capillaries, and lymphatics, is as
valueless as spilled milk; it can function only in its own
transportation system. That functioning depends, as does
cell and tissue metabolism, on the fact that the membranes
of cells and tissues have different degrees of permeability
to different substances.
In one sense blood itself is a tissue; it has its own metabo-
lism, it has its millions of living cells. But its main function
is transportation; it carries that out through the transporta-
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WHY WE BEHAVE LIKE HUMAN BEINGS
tion or circulatory system. That system maintains a day
and night service, remarkable as system and in the nature
of the material it brings to the door of the myriad cells of
our body. It does more than deliver: it collects poisonous
wastes and hands them over to the kidneys to get rid of.
That system breaks down with fatal results.
A 160-pound man has about eight pounds, or four quarts,
of blood. He may lose up to one and one-half quarts at one
time and recover. Within a day or two he has as much
blood as before; it may be a week before his blood regains
its former composition.
Under the microscope, blood is a pale yellowish fluid
in which float two kinds of minute cells, the red and white
corpuscles. The fluid is the plasma; 90 per cent water, 10
per cent reduced groceries and meats, chemicals, drugs. It
also contains many substances the physiologist is unable to
make or to isolate. Whatever it is that the endocrines
secrete, and whatever it is that enzymes are, the blood
transports them. It also transports such gases as oxygen,
carbon dioxide, and nitrogen; such inorganic salts as
chloride, carbonate, sulphate, and phosphate of sodium, cal-
cium, magnesium, potassium, and iron; such nitrogenous
extracts as urea, uric acid, creatinin, ammonia salts, amino-
acids, and phosphatives; many proteins; sugars, fats, lactates,
and cholesterol; five or six antibodies, and special substances
supposed to be concerned in the clotting of the blood.
Blood issuing from an open blood vessel (or drawn from
the body) clots, jells; this closes or seals the wound. This
clotting is a unique process, though gums play a similar
role in the vegetable kingdom. The very act of opening a
blood vessel seems to set up a reaction in the blood itself.
The blood contains an enzyme called thrombin (clot), which,
in shed blood, activates a soluble fibrinogen in the blood
to become an insoluble fibrin of very fine needle-like crystals.
Fibrin collects at the wound and permits the passage of
the watery serum, but holds back the red corpuscles and the
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THE PROCESSES OF LIVING AND THE GERMS OF DISEASE
platelets. They become enmeshed in the fibers, "clot"; the
opened blood vessel is sealed, the flow of blood is stayed.
But the white corpuscles squirm through the fibrin, as a
snake does through a brush heap.
Clotting may generally be hastened by hot towels or con-
tact with any foreign substance, by rest, and by the poison
from certain snakes. But the blood of some individuals
clots dangerously slowly; they may even bleed to death from
a slight wound. True hemophilia (bleeder's disease) is said
to be hereditary.
Clotting can be prevented by a secretion called hirudin
from the mouth glands of the pond leech; it is important
to a leech that its victim's blood should not clot! It is
important that our blood should clot when a blood vessel is
injured. Presumably the adrenal gland is responsible for
heightening the capacity of the blood to clot under certain
psychological stresses. But a foreign substance, even a
bubble of air, in a blood vessel may cause a clot, thrombosis.
If the blood can absorb the clot, no damage is done; if not,
and if the clot is carried to some point where it blocks circu-
lation, it is fatal. A clot on the brain or in the heart is
almost always fatal.
The personal service of collection and delivery is made
by the lymph, the body's middleman, the final link in our
transportation system.
We rarely see lymph. Rarely hear of it until it goes
wrong, then we know it as edema, or dropsy; if it is in the
legs, as elephantiasis — legs as big as elephants'. Something
stops up the lymphatics; lymph collects, the part of the body
affected swells up with lymph.
Lymph (water) is blood plasma that filters through the
microscopic walls of the capillaries. It bathes the cells and
effects exchange of materials, leaving behind what the cells
need, carrying off what is not needed. Then it joins the
great drainage system whereby blood is returned to the heart.
Lymph has its own system, lymph vascular system. This
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WHY WE BEHAVE LIKE HUMAN BEINGS
begins with minute lymph capillaries into which the lymph
passes by filtration. These unite in larger vessels, die
lymphatics; these empty into ducts which pour their contents
into two large veins which unite to form the upper vena cava.
Thus the blood has made a round trip: it is again in the
heart. Before it is put into general circulation again, it
must be aired.
Why do we not all have elephantiasis? What keeps the
lymph moving? Movement, for one thing. Every body
movement alters the shape and size of many muscles. This
puts pressure on the lymph vessels, which grow larger toward
the main ducts emptying into the veins. The lymph cannot
flow backward — or downhill, as it should because of
gravity — because the lymphatics are beset with valves, as are
the veins, especially in the arms and legs. The valves lie
flat against the wall of the vessels as long as the current
flows in the right direction. Reversing the current forces
the valves out and closes the tube. Lymph can only flow
in one direction, toward the heart.
In joining the larger lymphatics, lymph passes through one
or more of our 700 lymph-nodes. Some are no bigger than
pinheads, some as large as olive seeds. They abound in
the armpits, groins, thorax, neck, and mesentery. They are
not true "glands"; they secrete nothing. But they are our
good friends. They police the blood. Outposts held by
sentinels that never sleep; always on the lookout for foreign
substances, especially bacteria.
In fact, a lymph-node is barbed-wire entanglement for
bacteria ; they never get beyond a node without a fight. The
fight is bloodless, for neither combatant has any blood, but
it is always a fight to the death. Then it is that we discover
our lymph-nodes: the fight inside causes the node to swell
with inflammation. We met such inflamed nodes in child-
hood and called them "waxing-kernels."
The fight is between white corpuscles and bacteria. If the
cells win, we hear no more about it. If bacteria win, they
162
THE PROCESSES OF LIVING AND THE GERMS OF DISEASE
tell us. There is nothing so immodest or shameless as an
average bacterium, or can do so much good and so much
damage in proportion to its size. It can move mountains
and destroy cities.
If lymph is blood filtered through tissue, how do white
corpuscles get into lymph? The same way: they lengthen
and filter through. We hear much of these white corpuscles
or leukocytes (white cells). They are not well understood,
nor is it known how many kinds there are, where they
originate, how long they live, why they multiply — now
rapidly, now slowly — and what finally becomes of them.
Some are believed to originate in bone marrow, others in
lymph-nodes. They lead a fairly independent existence.
Presumably they break down dead tissue cells, carry fat
from the intestines into the lymph and so to the blood, help
stabilize the protein content of the blood, and possibly lib-
erate a substance which assists in blood clotting. They may
destroy the worn-out red cells in the spleen and liver. Some
eat bacteria.
Evidently bacteria au naturel are not palatable and some-
what indigestible. One kind of leukocyte is supposed to
remedy that. The blood plasma itself is credited with a
substance which makes phagocytes, as the "eater-cells" are
called, greedy for bacteria. This substance is called opsonin,
Greek for "preparing a banquet." With no opsonin in the
blood, a phagocyte eats only one bacterium at a time; with
opsonin, he takes them on in bunches, possibly because it
causes bacteria to herd. The result is the same: the
phagocytes engulf them faster.
Injury to or inflammation in any part of the body sets up
irritation. Blood hustles phagocytes up to the injured part;
it gets red from the red corpuscles of the blood. If bacteria
are present, a fight is on. If phagocytes win, they crawl
back into the blood again. If they lose, the bacteria kill
them and also tissue cells. Pus forms. Pus is dead tissue
and white corpuscles, plasma from injured blood vessels, and
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WHY WE BEHAVE LIKE HUMAN BEINGS
dead and living bacteria. A scar on the neck may mark
the spot where tubercular bacilli were held up by a lymph
gland and lost a fight with phagocytes.
Our "resisting power" is good when we have enough
leukocytes. We generally have enough when our transporta-
tion system is all in order.
10
The business of the transportation system is to deliver
fresh blood — "pasteurized," aerated, and heated to the
proper temperature — to several billion cells twice a minute,
every minute of life. That is big business and of vital
importance; and no man-made transportation system comes
within miles of it for honesty, accuracy, or efficiency. Nor
has man yet made as fine a tube as an artery or as good a
pump as the heart.
Cut a thin section across a small artery and put it under
a microscope. It has three coats of muscle. The fibers
of the outer coat run lengthwise and are dense; they
strengthen the artery, enable it to resist undue expansion,
make it hard to cut or tear. The inner or lining coat is
extraordinarily smooth; the blood hustles on with next to no
friction. The middle coat is in two layers of fine muscle
fibers circularly interlaced ; one layer is elastic, the other con-
tractile. The thickness of this coat varies according to the
traffic it bears; the larger the artery, the thicker its walls.
With every heartbeat, every inch of artery in the body
expands and contracts. In fifty years they have expanded
and contracted about three billion times. When this middle
coat clogs up with lime salts they harden, lose their elasticity.
Arteriosclerosis probably increases the rate of flow in the
arteries — but does not make for "high blood pressure." Fat
does.
Arteries carry blood from the heart. The great artery,
or aorta, leading direct from the heart, is about an inch in
164
THE PROCESSES OF LIVING AND THE GERMS OF DISEASE
diameter. It soon branches; the branches branch; on and
on; they become smaller, smaller, and finally discharge their
tiny rivulets into capillaries so minute that it would take
thousands of them to hold as much blood as the aorta. Even
the corpuscles in the blood must travel through them Indian
file, and at that it is often a tight squeeze.
The heart is simply the central power house; the arteries,
simply the tubes. But with the capillaries the transport
system becomes a special service; without them, the blood
could not do its big work. They form a vast network through-
out the entire body except in hair, nails, cuticle, cornea of
the eye, and cartilage; that is why cartilage is so white.
The blood returns through veins, also tubes and very tiny
at first where they begin to gather up the minute trickles
after the blood has done its work in the capillaries. The
tubes grow larger and larger as vein after vein keeps dis-
charging its contents, and become at last the two great vence
cavcB which deliver the blood to the heart.
The heart is easily understood if one does not look at it;
then it seems hopelessly complicated. Think of it as two
pairs of cubes, one pair on top of the other. The two top
cubes are shaped like ears, hence their name, auricles. They
receive blood: the left auricle, from the lungs by means of
the two pulmonary veins; the right auricle, from the upper
and lower part of the body by the two vence cavce.
The two bottom cubes are round like little bellies, hence
their name, ventricles. They expel blood: the left ventricle,
to the body via the aorta ; the right ventricle, to the lungs via
the pulmonary artery.
Why does the heart beat 75 times every minute? How
does the blood know where to go? The second question is
easy, the first is now being solved.. But beat it does, from
four months before birth until life snuffs out with its last
beat. Forty million times a year. The work it does is
literally staggering. More amazing is the fact that it will
go right on beating after it has been removed from the body;
165
WHY WE BEHAVE LIKE HUMAN BEINGS
kept moist in a neutral salt solution (sodium, calcium, and
potassium salts) and fed a little sugar, it will beat for days.
Muscle tissue cut from the body will also grow and beat
rhytlimically under stimulus, but there is an automatic action
to the heartbeat which as yet has not been solved.
The heart is striated and "involuntary" muscle — not
under control of the will. Only the heart has this combina-
tion. The result is a specific dynamic system which functions
in connection with certain nutrients and ions. Seventy-five
beats per minute is a normal average; but among the soldiers
of a single company, all presumably normal and all under
similar conditions, it was found to vary from 42 to 108.
The heart beats according to its past as well as to its
present experiences; emotions, diseases, narcotics, drugs,
muscular activity, rate of metabolism, etc., all enter into the
count. The bigger the body, the slower the beat: 25 per
minute for an elephant; 50 for a donkey; 70 for men; 80
for women; 90 for youth; 140 for a newborn; 150 for a
rabbit; 175 for a mouse. The more active the body, the
faster the heartbeat. I can save my heart 20,000 beats a
day by remaining quietly in bed. It has been experimentally
determined that when the pulse is forced up to 135 per
minute, the subject becomes uncomfortable; above 160 it is
very distressing and fairly unbearable, although one was
recorded of 184 per minute.
The blood-stream is kept to its course by valves. For
example, blood returned from the body by the two vencs
cavce fills the right auricle and the right ventricle: the two
at the time are one chamber. The auricle contracts, forcing
more blood into the ventricle below. As the contraction
slows up, a valve between auricle and ventricle is forced
shut by the pressure of blood in the ventricle. This ventricle
now contracts, forcing the blood through the now open valves
into the pulmonary artery and so on into the lungs. It is
returned by the pulmonary veins, and enters the left auricle
and ventricle. Left auricle contracts, distending the left
166
THE PROCESSES OF LIVING AND THE GERMS OF DISEASE
ventricle; then the valve between them closes. Then the left
ventricle contracts, forcing the blood into the aorta. After
it has traversed the body it is returned by the vence cavce to
the right auricle.
Around it goes. It cannot go astray, for it circulates in
a closed system; valves in the heart and in the veins prevent
it from going in the wrong direction. The heartbeat forces
it to keep moving. The vasomotor apparatus, through nerve
connections with the muscle walls of the arterial system,
controls the amounts of blood flow to the various tissues and
organs of the body.
This transportation system must supply its own needs also.
Arteries and veins are tubes of living tissue; they must have
their blood. They receive it from their own system of
arteries, capillaries, and veins: the vasa vasorum, blood
vessels which supply nourishment to the coats of other blood
vessels.
11
The left half of the heart contains arterial blood; the
right, venous. The walls of the two auricles are relatively
thin; of the ventricles, thick — that of the left three times
that of the right; it has three times as big a job. The left
ventricle drives blood into the aorta with a velocity of about
thirty feet a second. But before that blood returns to the
left ventricle, it must make two long journeys. First it visits
every nook and cranny in the body, and is returned by the
vence cavce to the right auricle. That completes the systemic
or general circulation and requires twenty-three seconds.
From the right auricle the blood passes down into the
right ventricle, and by it is driven through the pulmonary
arteries to the lungs. There it takes the air. It then returns
by the two pulmonary veins to the left auricle, and thence
into the left ventricle. That completes the pulmonary circu-
lation and requires about fifteen seconds. The blood is now
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WHY WE BEHAVE LIKE HUMAN BEINGS
ready to be expelled by the left ventricle into the aorta, to
be put again into general circulation.
"Taking the air" is a vital process — in fact, no process is
more vital; but before looking at it, let us see how the new-
born prepares for that momentous first step, one of the most
interesting adaptations in life.
The four-months-old fetus is attached by its umbilical
cord to the now fully formed placenta, consisting largely of
connective tissue and blood vessels which interlace with
blood vessels in the uterus. But there is no direct exchange
of fetal blood with that of the host; only by diffusion through
permeable membranes can the fetus derive nourishment and
oxygen from its host's blood vessels. This it does through
the umbilical vein. Through the two umbilical arteries it
delivers to the placenta the end-products of fetal metabo-
lism— chiefly carbon dioxide, which diffuses from placental
blood vessels into the blood vessels of the host and is by her
eliminated in her lungs.
After birth, the umbilical cord is tied and cut. This cuts
off the newborn's oxygen intake and carbon dioxide outlet;
it must make vital rearrangements. Quick.
A blood clot forms between the navel and the liver in what
was the umbilical vein; that stops circulation in that direction
and prevents the infant from bleeding to death. As a result
of that clot, two blood vessels cease to function and pass off
the stage forever. Another clot forms in the vessel which
connected the aorta with the pulmonary artery; and it goes
out of circulation. Two other clots form; and two other
vessels begin to obliterate themselves.
One other change is necessary before the infant is a full-
fledged air-breather. Up to the time of birth there is an
opening between the right and left auricles, the foramen
ovale. But with the closing of the vessel from the pulmonary
artery to the aorta the blood is forced into the lungs, thence
into the pulmonary veins, thence into the left auricle.
Pressure in the left auricle closes the foramen ovale between
168
THE PROCESSES OF LIVING AND THE GERMS OF DISEASE
the two auricles. It stays closed; thereafter there is no
opening between left and right auricles. Sometimes it does
not close tight; venous blood mixes with arterial. The
result of this mixture is impure blood; cyanosis — "blue
babies," even blue adults. If the opening is too great, the
mixture is fatal; not enough blood gets the air.
This separation of the heart into right and left halves,
thereby keeping venous from arterial blood, made constantly
warm blood possible, and is found only in birds and mam-
mals. Lower vertebrates have impure blood, and change
their temperature with the thermometer. Failure of the new-
born's foramen ovale to close is a memento of reptilian days;
death follows because our metabolic processes are set for
pure warm blood.
The clots and the closure of certain blood vessels and
foramen ovale completely alter the newborn's circulation;
it must now get its oxygen by its own efforts. It draws its
first breath.
This is a big job for a small child. Lungs at birth are
solid; they must be shaken out, filled up, as one would a
balloon. The balloon the infant has to fill is several times
larger than its body. Lungs are like enormously complex
sponges — minute pockets or air cells, all opening into fun-
nels, these into tubes or bronchioles, these into right and left
bronchi, these finally into the trachea or windpipe.
Trachea and bronchi are lined with the microscopic
chimney-sweep cilia. They move foreign particles up within
reach of the coughing mechanism. When the cilia are
damaged by bad-cold germs, we cough up floods of mucus,
dead cilia cells.
If the infant takes its first breath through its nose, it sets
a good example for itself; that is what the nose is for.
Internal-combustion engines work best if given warm air.
The infant is such an engine. Its nose is like a scroll radi-
ator, thereby exposing a large area of membrane to contact
with its first and every breath. That breath drawn through
169
WHY WE BEHAVE LIKE HUMAN BEINGS
the nose filters, warms, and moistens the air, important
qualities for every breath. The nose prepares the air for
the lungs as the mouth prepares food for the stomach. It
"samples" air by the sense of smell, as the mouth samples
food by the sense of taste. If the air is no good, we hold
our nose ; if the air is cold, the vasomotor system sends more
blood to the nasal membrane.
The infant is in contact with the air through the skin of its
body. When its lungs are expanded, another surface is in
contact with the air; this lung surface is from ninety to one
hundred times greater than body surface. An average man
has about one square yard of skin surface, about ninety
square yards of lung surface.
12
After our first breath, our lungs are never again free from
air. They must have thin walls, to let oxygen into the blood
and carbon dioxide out; without air they would collapse.
The passages leading to the air-sacs do not collapse, because
they are held open by stout rings of cartilage. Even if
removed from the body and punctured, the collapse of the
small tubes entraps air into the air-sacs. Lungs that will
float cannot have belonged to a stillborn; butchers call them
"lights" — they are lighter than water.
There are always about two pints of residual air that we
cannot budge. But with great effort we can expel the sup-
plemental air — about three pints. With no effort at all we
inhale and exhale tidal air — about one pint. With another
effort we can inhale about three pints more — complemental
air. The maximum amount of air that can be forcibly
expelled after a deep inspiration is about one gallon. This
is vital capacity; it differs with individuals, and diminishes
if we give our lungs no hard work to do.
We breathe faster when a certain nerve center in the brain
tells the inspiration muscles to speed up. The nerve gets
170
THE PROCESSES OF LIVING AND THE GERMS OF DISEASE
its cue from carbon dioxide. There is always carbon dioxide
in the blood, but it plays second fiddle to oxygen. When
there is too little oxygen or too much carbon dioxide, we
breathe faster. The air we inhale has 21 per cent of oxygen,
.04 per cent carbon dioxide. The air we exhale has 16
per cent oxygen, 4 per cent carbon dioxide, which means
that in the lungs the air lost 5 per cent of its oxygen and
gained 4 per cent carbon dioxide. No matter how cold and
dry the inhaled air, the expired air is blood hot and saturated
with moisture.
A thin, moist membrane of the lungs separates air from
blood. On the air side is a high percentage of oxygen. On
the blood side, a high percentage of carbon dioxide. An
exchange of gases takes place through the membrane. As a
result, the blood brought to the lungs by the pulmonary
arteries loses about 10 per cent of carbon dioxide; the blood
carried back to the heart by the pulmonary veins gains about
10 per cent of oxygen.
It requires less than two seconds for the blood to take the
air and exchange its crimson for a scarlet hue. Arterial
blood is scarlet. If "blue" blood is a caste sign, certain
shell-fish are the Brahmins of creation; their blood oxygen-
carrier is not the iron of hemoglobin, but the copper of
hemocyanin. This copper is blue in the crab and tastes like
copper in the European oyster.
Aerated blood begins its long round through the body as
soon as it is shot into the aorta by the left ventricle. The
blood delivers its oxygen as the iceman leaves ice — according
to the needs of families on its route, making the round trip
every half minute. An organ, gland, muscle at rest does not
need much, but activity anywhere — in organ, gland, muscle,
what not — means an extra supply. The heart itself will use
twice the oxygen at one time it does at another. At meal
times the intestines require extra large supplies. Even mild
thinking causes the brain to double its usual demand. "Fast
thinking" may even require fast breathing. Whatever con-
171
WHY WE BEHAVE LIKE HUMAN BEINGS
sciousness is, it goes out like a candle when the oxygen is
cut off.
Oxygen. Oxygen. Everywhere we go, every time we turn
around, always, as long as we live, the tissues of our body
are crying for oxygen and freedom from carbon dioxide,
else they choke to death. And our bellows keep working
away: 60 breaths a minute for the newborn, 40 for the child,
20 for the adolescent, 16 to 18 for the adult. About one
breath for every four heartbeats is a normal average.
The air we breathe is about 80 per cent nitrogen; as it is
an inert gas, we absorb none of it. But under high atmos-
pheric pressure, as in a diving bell or caisson, nitrogen is
dissolved in the blood and in the tissues. If the pressure
is suddenly released, the gas cannot remain in solution but
forms bubbles, and the blood effervesces like a bottle of pop.
(A nitrogen bubble lodged in a vital spot is as fatal as a
blood clot.) This makes for stiff muscle joints — "bends,"
the workmen call them. If the pressure is slowly relaxed,
bubbles do not form, and the gas in the tissues is carried
by the blood to the lungs and nitrogen equilibrium with the
gases of the atmosphere is again restored.
Equilibrium. The body is wonderfully balanced. Vital
processes other than growth are equilibrizing processes.
When the equilibrium is upset, the body begins to readjust.
It works like a defensive army, massing its forces against
the greatest dangers. The blood is the marvelous distributor,
regulator, restorer, provider, of forces. When one thinks
of the billions of individual cells the blood serves, it is truly
the Little Friend of All the World.
It is significant that too much carbon dioxide rather than
too little oxygen sets the bellows working faster. If we are
only short of oxygen we can fall asleep, even in death; the
lungs rise and fall until the last. We can burn ourselves
up slowly; but from the smoke of the fires of action we must
be promptly delivered.
Not, Give the lungs air; but. Give the air carbon dioxide.
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THE PROCESSES OF LIVING AND THE GERMS OF DISEASE
That purifies the blood. And if respiration cannot be
resumed otherwise in an asphyxiated person, give his respira-
tory center carbon dioxide — then it will order the lungs to
action. But if the respiratory center is dead, it is too late.
13
Abel withdrew from one dog in one day twice the volume
of its blood. The dog should have died twice, but inasmuch
as the professor collected and returned all its red blood
corpuscles, it lived. When he withdrew only 60 per cent
of the dog's blood and did not promptly restore the red
corpuscles to its blood, it died.
Our lungs are valuable, but we really breathe through the
hemoglobin, or respiratory pigment of the red corpuscles.
Blood plasma is complex; the red corpuscles, or erythrocytes
(red-cells), are inconceivably complex. They are born in
the red marrow of bones and have nuclei as have other
cells. On entering the blood stream they lose their nuclei
and assume their characteristic disk or muffin shape; they
can no longer grow, and, after ten or fifteen days' work, die
and are broken up in the liver or spleen. In fishes, amphibia,
and camels, the nuclei are not lost in the blood.
Each red corpuscle is about 1/3200 of an inch in diameter,
1/12400 of an inch thick. Yet they make up about 35 per
cent of the volume of the blood — or enough to fill a pint cup.
In a spoonful of blood there are about 30,000,000,000, or
in an adult male about 25,000,000,000,000; a few billions
less in an adult female. Her blood and her lips are no less
red, nor has she less capacity to blush or acquire a red nose,
nor has she less iron -in her constitution; simply less body,
and consequently need for less blood. Anemic persons have
either fewer red cells or less iron in the cells they have.
The proportionate number present at any one time varies
according to many factors — constitution, nutrition, and
especially with age, being most numerous in fetal life. In
173
WHY WE BEHAVE LIKE HUMAN BEINGS
women, they increase in number during menstruation, dimin-
ish during pregnancy.
Red blood-cells carry oxygen. That makes them red and
they make the blood red. They are soft, flexible, elastic.
Had a camel these qualities equally highly developed, he
could easily pass the needle's eye. Carried by the blood to
the lungs, they squeeze through spaces as small as the uni-
verse is big, resuming their disk-like shape. With nothing
between them and the air but a thin membrane, they detach
oxygen and squeeze through into the blood again. They are
small, but their combined surface area is nearly 4,000 square
yards, with nearly 90 square yards of lungs for them to
operate on. Of course, only a small portion of them are
present in the lungs at any one instant. The blood lugs them
about from cell to cell. Any cell needing fresh air then and
there gets it; and gets rid of carbon dioxide, which the blood
carries to the lungs. If it carries much we take a long breath,
or several.
While it has long been known that the hemoglobin carries
oxygen, it has only recently been established that it also
carries most of the carbon dioxide. According to Du Bois,
sufferers from faulty circulation show lack of oxygen and
excess of carbon dioxide; their blood does not move fast
enough through the lungs for the red-cells to get rid of their
carbon dioxide. When the saturation of oxygen in venous
blood falls below 20 per cent, cyanosis results.
Ordinarily, it is not lack of oxygen or excess of carbon
dioxide in crowded rooms that makes for distress; it is the
heat, humidity, and odors of unwashed bodies. Gases diffuse
through insignificant cracks in walls, around windows, under
doors. It was the heat and humidity that were so fright-
fully fatal to the crowd in Calcutta's Black Hole, not lack
of oxygen or excess of carbon dioxide.
While the air we breathe ordinarily contains about .04 per
cent of carbon dioxide, a submarine crew will work for days
in air containing 2.5 per cent and suffer no ill effect. With
174
THE PROCESSES OF LIVING AND THE GERMS OF DISEASE
5 per cent carbon dioxide in the air, we double our rate
of breathing; when it rises above 8 per cent, we are in real
distress. Further increase begins to slow up the rate of
breathing, with death when it reaches 40 per cent.
Too much oxygen is equally fatal. Ordinarily, air con-
tains about 21 per cent of oxygen — more than we need or
can use. Nor does breathing pure oxygen increase the
oxygen-content of the hemoglobin (oxyhemoglobin). But
pure oxygen at a pressure of three atmospheres (one for
every thirty-three feet) leads to convulsions and death.
Workers in caissons, diving bells, and submarines may die
from oxygen poisoning in ordinary air at five atmospheric
pressure; fifteen atmospheres is always fatal.
At about 26,000 feet above sea-level, the oxygen concentra-
tion falls to 7 per cent — a test for an aviator's fitness. Even
at 15,000 feet many suffer severe "mountain sickness"
(anoxemia), and lose consciousness above 20,000 feet. But
by compensatory action in heart and blood vessels, most
people can soon become "acclimated" to mountain heights.
Just how the respiratory pigment jettisons carbon dioxide
and takes on a cargo of oxygen while in the lungs is no more
known than just how an ameba or a cold potato breathes, or
how the cells of the tissues of our body exchange carbon
dioxide for oxygen. But they do, and we breathe easier.
In one red blood-cell are unnumbered millions of millions
of molecules of hemoglobin. Each molecule is of huge size
and of such complexity as to baffle the imagination. Here
is its supposed molecular formula: C758Hi203Ni95S3FeO2i8;
molecular weight, 16,669. Only three atoms of sulphur, one
of iron. But iron is iron and a little of it goes a long way
in the affairs of life — and leads to some amazing perform-
ances.
Most of hemoglobin is globin, a protein, as might be
inferred from the nitrogen and sulphur in the molecule. The
remaining 5 per cent is iron salts or hematin with a com-
paratively simple molecular formula of G34H34N4Fe05. That
175
WHY WE BEHAVE LIKE HUMAN BEINGS
hematin will crystallize we have seen ; the crystals themselves
are as specific for species as are starch grains. A horse's
hemoglobin crystal no more looks like that of a human being
than a man looks like a horse; but a mule's crystal is half-
way between that of a donkey and a horse. Why not? There
are such relationships as blood.
Blood is blood and that of all mammals has the same
constituents in about the same proportions. Yet blood is
specific for different species, and the amount of difference
suffices to prove that man is closer blood kin to Old than to
New World monkeys. By means of a blood test it was
proved that the malaria-carrying mosquito feeds on pigs and
cattle as well as on man; by that test horse-meat has been
distinguished from beef; blood on a cleaver proved to be
deer's blood, and not wild duck's, as the man accused of
poaching swore it was; and a stain was proved to be human
blood after a lapse of sixty-six years.
All of which opens up a large vein in life — ranging from
murder trials to immunity from bacteria.
Any foreign protein element in a blood-stream is a foreign
body, an antigen. An antigen will provoke an antibody. A
foreign red blood-cell is an antigen; the antibody it provokes
is a hemolytic, a dissolver of foreign red blood-cells. Bac-
teria in a blood-stream are antigens; the blood's reply is
four kinds of antibodies: opsonin, makes them tasty to the
phagocytes; agglutinin, causes them to herd together and
consequently likely to be engulfed in lots; precipitin, causes
them to settle down or precipitate when held in solution;
and lysin, which dissolves bacteria. Lysins, opsonins,
agglutinins, precipitins, etc., are specific antibodies, chem-
ical systems which induce specific reactions. When bacteria
are agglutinated, thinks Jordan, their negative charge of
electricity is reduced; they are thereby more subject to the
precipitating action of salts. The net result of the action of
the antibodies is to destroy the antigens or so alter their
176
THE PROCESSES OF LIVING AND THE GERMS OF DISEASE
nature that they are more easily handled by the phagocytes,
or police of the blood.
Bacteria, red blood-cells, spermatozoa, even pepsin,
injected into the blood-stream, evoke specific antibodies; one
kills the bacteria, one dissolves red blood-cells, one disinte-
grates spermatozoa, one neutralizes the enzyme pepsin. On
this capacity of the blood (and of other tissues) to react to
antigens is based the whole practice of acquiring immunity
in bacterial diseases by the use of cell-dissolving sera.
Is it human blood? If there is enough of it the question is
easily answered; injected into the body of a rabbit, the rabbit
dies. But suppose there is only a drop of it, or the decom-
posed remains of one blood clot? The test is simple. Into
a rabbit or similar laboratory convenience inject a non-
lethal dose of human blood (or ape's — they are so closely
related they are almost twins). The rabbit's blood develops
a specific antigen for human red blood-cells — it is immune
against human blood. To some of this rabbit's immune
serum add the "suspect," and incubate; if there is a flocculent
precipitate, the suspect blood is human (or ape) blood.
Is it blood? There may be only a stain on the floor, a
shred of stained cloth, or perhaps only one drop of water
left in the bottom of the tub in which the suspected murderer
bathed. Such tests for blood can be made. They depend
on the ability of an inconceivably small amount of hemin
to make itself known by showing its specific color when sub-
mitted to delicate chemical tests.
14
Breathing is action in a mechanism and implies work; and
that suggests heat. Only at absolute zero do molecules cease
to vibrate. They cannot vibrate; they have no heat. Heat,
in other words, is a form of energy. And a thermometer
is a device for measuring its energy.
For example, the heat under my tongue at this moment
177
WHY WE BEHAVE LIKE HUMAN BEINGS
suffices to expand mercury (raise its temperature) until it
registers 98.36 degrees. The heat of the skin of my hand
is not so great; it would be even less if I were making snow-
balls. But the temperature at this moment of my body in
general is not far from 100 degrees; call it 100 for short.
Heat, as we saw, can also be measured in terms of cal-
ories— one calorie being the amount involved in raising the
temperature of about two pounds of water about two degrees.
If my temperature is 100 degrees, my body contains a certain
number of calories — ^heat or energy units. Suppose I drop
dead; my body begins to cool. If it is in a warm room it
will lose 550 calories within twenty-four hours; if in a cold
room, 1,000 calories. Where has the heat gone? WHiere
does the heat of a red-hot poker go? Same place. It has
flowed out, radiated, been conducted. My dead body in a
room with a temperature of 100 degrees would lose no
calories — there could be no flow of heat, because heat flows
only from a region of high to a region of low temperature.
But suppose I am not dead yet, but have only lost a leg;
my temperature remains about the same, but I have dimin-
ished the calories in my body — I have less body. Heat
would still be conducted from my body; there would not be
so much heat to conduct.
Heat, being a form of energy, does things, causes change —
a rise in temperature, a change in state, a chemical change,
etc. If I apply enough heat to a piece of coal, its carbon
finally combines with the oxygen of the air: it burns; I need
apply no more heat — the heat developed by the oxidation of
the carbon will suffice to continue the reaction until the carbon
is all oxidized.
Our daily intake of fuel-food is, let us say, 2,500 calories.
Assuming that we are not taking on fat, but just holding our
own, what becomes of these 2,500 calories? If at the end
of the twenty-four hours we have neither gained nor lost
weight, and have added 2,500 heat units to a body already
at a temperature of 100 degrees and it is still at that same
178
THE PROCESSES OF LIVING AND THE GERMS OF DISEASE
temperature, these ingested calories must be somewhere —
and they cannot be inside us. We lose them in two ways:
radiation and conduction from the skin, about 73 per cent,
or 1,795 calories; through loss of materials from our body,
about 27 per cent, or 705 calories. Whatever leaves our
body carries with it body-temperature heat. Thus through
saliva, excreta, etc., we lose about 50 calories; through
expired air, about 265 calories; and by sweat, about 365
calories. These are all heat losses, means of ridding the
body of the heat liberated in the 2,500 calories of ingested
food.
All this is simple enough. It is equally obvious that
engines work best under certain temperature conditions.
Motor engines must be protected from too great heat by
cooling devices, airplane engines from too great cold by
heating devices. A big tree will sweat a half -ton of water
on a hot day to keep its temperature down. Our body engine
will not work at all if our temperature varies a few degrees
from normal. We freeze to death when we cannot make
enough heat, and die of fever or sunstroke when we cannot
get rid of enough heat. At 105 degrees enzyme action
ceases through autodestruction, the brain engine cannot work;
above 105 degrees, the brain begins to be destroyed.
Which means that our body functions best at a certain
average temperature. When our temperature varies more
than 2.5 degrees from that normal average, our oxygen
metabolism is upset and our body is abnormal. We birds
and mammals are not so much warm-h\oode6. animals as we
are constant-lem^exdiXme animals.
How does our body so regulate its heat production and its
heat loss that its vital parts are kept at a practically constant
temperature? It is easy enough to see how ingesting more
calories, taking more exercise and consequent burning of
stored calories, and clothing keep us warm even though we
are breathing the frosty air of 40 below zero; but how do
179
WHY WE BEHAVE LIKE HUMAN BEINGS
we keep cool when the thermometer stands at 120 — as they
do in Death Valley?
Simply by getting rid of more heat.
Heat loss through expired air is fairly constant and little
subject to change in outside temperature. Expired air is
always warmer than inspired air; it is almost saturated with
vapor. We expire about a pint of water a day; each gram
of water vaporized required one-half of a calorie, 180 in all.
To warm the inspired air consumed 85 calories.
The blood is the go-between for all parts of the body.
Heat generated in any part of the body will heat the blood
that passes by. The water in the blood is the transporter and
distributor of heat. But the blood also reaches about sixteen
square feet of skin and about ninety square yards of lung
lining. In both skin and lungs it comes close to outdoor
temperature. Through the vasomotor nerves the supply of
blood to the skin is under automatic reflex control. The
vasomotor system, then, is the principal regulating mecha-
nism. In air close to body temperature there can be but
little loss of heat from skin by radiation and conduction;
in cold atmosphere the loss will be excessive. The vasomotor
system must arrange for compensation. The details are not
yet known, but the results can be seen.
Sweat, for example. We have about 2,000,000 tiny pores,
or sweat-glands, in our skin, about 500 to the square inch,
about 2,000 per square inch in the palms of our hands and
the soles of our feet. Sweat is 99 per cent water, 1 per cent
salt, a small portion being urea. An average man on a
mild summer day will sweat about two pints. He can sweat
as much as ten pints; in that case 10 per cent of his urea
excretion would pass out through the sweat-glands.
Cats and dogs do most of their sweating through pads on
their feet. A dog also opens his mouth wide and sweat —
in the form of saliva — drips from his outstretched tongue.
Both dog and man also pant, thereby increasing lung ventila-
tion. If the outside humidity is not great, panting increases
180
THE PROCESSES OF LIVING AND THE GERMS OF DISEASE
the amount of evaporation of water from the blood in the
lungs.
In the dry air of Death Valley deserts, with the temperature
at 120, we do not "sweat a drop." We do; the sweat evap-
orates as fast as it is secreted. On hot, moist days it
evaporates slowly because air can only take up so much
moisture. Moist air itself is a fine conductor of heat. Hence
more sunstroke with moderate heat and great humidity than
with great heat and slight humidity.
Sweating, then, is an active transfer of fluid from inside
the body to the surface of the body, where it is vaporized,
a heat-consuming process. The sweat that is not vaporized
drips from the skin, but, as Du Bois points out, it "removes
no heat from the body except as it diminishes the weight
of the body." Sweating is a different matter from the mere
evaporation of water from a non-sweating skin.
When air temperature reaches 86 or more, or when ordi-
nary vaporization from lungs and skin and the amount which
can be lost by radiation and conduction falls below the
amount of heat that must be eliminated, the sweat-glands
begin to pour out water. Actual sweat is the body's last
resort in keeping down the temperature. A flushed face
covered with sweat is a skin losing hot water because it cannot
lose steam fast enough. Usually our skin is "slightly moist,
moister than a dead animal, not as moist as meat in a butcher
shop."
The actual secretion of sweat is controlled by sweat nerves.
The secretion itself increases the heat loss. Rarely individ-
uals are found without sweat-glands — icthyosis hysterix.
They cannot work in summer or in heat where a normal man
would sweat. In one well-known case even slight work would
send the individual's temperature up to 105 degrees.
There is always blood in the skin. On warm days the
capillaries are gorged with blood; if the air is not too hot,
much heat is lost by radiation and conduction and by vapori-
zation. On cold days the blood is withdrawn from the skin;
181
WHY WE BEHAVE LIKE HUMAN BEINGS
as Du Bois says, we change our skin into a suit of clothes
and withdraw the zone where the blood is cooled to a level
some distance below the surface.
This change in volume (and possibly in concentration) of
peripheral blood is a matter of vasomotor function, but what
part the hot and cold points in our skin play is not yet known.
When air below 60 degrees strikes an unprotected body, the
cold points are stimulated. They tell the muscles to shiver;
that is their way of getting warm. Shivering is a heat-
producing device. Presumably the blood itself has become
more concentrated, water has been withdrawn; it is
"thicker" — less heat is carried to the radiating surfaces. A
man up to his neck in a bath of 104 degrees stops sweating
on his forehead as soon as one hand is plunged in cold
water. Same reason. Sweat-gland nerves also work accord-
ing to temperature stimuli. The cold point nerves now cry
louder than the hot point.
Heat production is a chemical regulation — action in
neuromuscular system, action of food on metabolism; heat
loss is physical regulation — sweat centers and nerves, vaso-
motor center and nerves, respiratory center, water-content of
the blood. So marvelously do these mechanisms work in
harmony, and so wonderfully are they co-ordinated, that
Howell believes it necessary to assume the existence of a heat-
regulating center in the brain. WHiere it is and how it works,
if there is such a center, are not yet known. It is assumed
that that center is upset during fever.
Temperature above normal not caused by food, work, or
outside temperature, is fever. The cause of fever is not
known.
We sometimes shiver during a fever. Fever disturbs the
vasomotor system; the blood supply to the skin is reduced.
This makes the skin cool. Its "cold points" are stimulated.
The blood concentration is increased; this may be useful in
overcoming the effects of toxins in the body. A rise of two
degrees of temperature in one hour means an increase of
182
THE PROCESSES OF LIVING AND THE GERMS OF DISEASE
fifty-eight surplus calories stored in the body. The body,
as Du Bois puts it, has become a reservoir in which extra
heat is stored; it is released when the temperature of the
body falls two degrees.
Subnormal temperature accompanies starvation; less heat
produced because less oxidation. The body has run out of
good fuel; it begins to burn itself; its proteins are not good
fuel, they do not oxidize well. First to go are the glycogen
deposits, next the stored fats. Intestine, lungs, pancreas,
brain and spinal cord, and heart, go last of all, and in the
order named. Heart last of all. Even the liver is of little
use to a starving man but as firewood; half of it is burned
up before the heart has contributed more than 2 per cent of
itself to the smoldering flame. Twenty-five per cent of the
blood of the body may be found in a normal liver; its activity
releases much energy, it is a reservoir of heat. But robbed
of its materials, it is an idle shop. The starving body burns
it to keep the brain and heart warm. In all the world of
warm blood there is nothing so dead as a cold heart.
15
Glands are no more unique in life than any other structure
or organ evolved for living purposes. We find no glands
in an ameba, but the ameba has a full set of test tubes for
chemical reactions. At any rate, it oxidizes carbon for vital
purposes and synthesizes dead into living protoplasm. A
cow also does that, and manages to get most of the neces-
sities of life into her milk; her milk will rear a calf.
Her body and ours are organic wholes, held together for
reaction purposes by a nervous system, held together for
growing and living purposes by the blood. Into that blood
all the cells of the body dip their fingers for what they
require; into it they dump what they do not require or what
they have made that other parts of the body may require.
So it comes about that certain groups of cells are organized
183
WHY WE BEHAVE LIKE HUMAN BEINGS
to clear the blood of refuse, other groups to deliver to the
blood or to the alimentary canal chemical reagents, enzymes,
and regulators.
These special groups of cells are called glands — Latin for
acorn. Any organ in the body which secretes something the
body needs, or excretes waste which otherwise would be
injurious to the body, is a gland. I keep moving my elbow;
it does not wear out; certain glands secrete elbow oil. Bones,
muscles, organs, all contribute to, all benefit by, the scheme
of the secretions of glands.
Our body contains literally millions of glands. Some are
endlessly duplicated — sweat, oil, and intestinal glands;
others are single or in pairs. Some always work; others
work only part time. Some function only for a certain period
during life and then slink away, like actors who appear dur-
ing one scene only. Some serve a double function, like the
liver and the glands of reproduction. Some secrete definitely
known substances; others have no known secretion. Some
have a canal or duct by which their secretions are delivered
to definite organs; others are ductless.
Our skin is thickset with two kinds of glands which have
ducts or canals. About 2,000,000 sweat glands secrete
water and so help to regulate our temperature. Fat or
sebaceous glands, usually one for each hair, help to protect
the body from cold and the hair from becoming brittle.
Lachrymal glands secrete tears through ducts which wash
and lubricate the eyes. A duct on the inner corner of the
eye drains the dirt-laden tears into the nose, if not secreted
too fast; then they spill over the eyelids.
Our alimentary canal is beset with food-digestion glands.
Parotids in the cheek, sub-linguals at the base of the tongue,
and sub-maxillaries in the lower jaw, "make our mouth
water," preparing food for digestion and acting as a ferment
to convert starch into sugar. The big glands of food digestion
are the gastric glands, pancreas, and liver. The pancreas
secretes ferments that digest fats, carbohydrates, and pro-
184
THE PROCESSES OF LIVING AND THE GERMS OF DISEASE
teins. The liver, largest of our glands, secretes bile, forms
urea, and stores glycogen.
The secretions of all these glands are carried by ducts to
other organs or systems. They are known as the duct, or
exocrine, glands. They deal with the upkeep of the indi-
vidual. On their proper functioning depend in general food
digestion and the protection of the body from extremes of
temperature and of the eyes from motes. But there is an
important difference between the glands of food digestion
and the glands which water the eyes, oil the skin, lubricate
the joints, and regulate the temperature. Food-digestion
glands secrete definite chemical substances, manufactured
within the glands themselves.
Some of these chemicals are manufactured in large quan-
tities— ^hydrochloric acid, for example, by the stomach.
Other chemicals are produced in amounts so small that they
are only with difficulty discovered by the physiologist; such
are the enzymes. These chemicals are prepared by the
glands from the nutrient solutions carried to them by the
blood. It is their business to pick them out and combine
them into such products as in the course of evolution they
have become adapted to produce. They must be plentifully
supplied with arterial blood.
The primary function of the duct glands, then, is to keep
the body fit and to supply it with tools for razing dead
bodies so that their debris may be built into living bodies.
To that extent they are concerned in growth and the proper
functioning of the body mechanism. But the control of
growth itself and the determination of the character of the
body mechanism depend on other glands — the endocrines —
whose nature until recently was not even suspected.
The kidneys are not glands of secretion; they secrete
nothing. They are excretory organs. Their function is to
filter from the 500 quarts of blood which flows through them
every twenty-four hours, poisonous nitrogenous wastes, salts,
and enough water to carry them in solution through the
185
WHY WE BEHAVE LIKE HUMAN BEINGS
ureters to the bladder. The kidneys are indirectly con-
trolled by the vasomotor nerves, more directly by chemical
stimuli in the blood itself. Increase of oxygen to the
kidneys, for example, decreases urine secretion. Substances
such as urea are always filtered out of the blood by a normal
kidney, but sugar, chlorides, and sodium are excreted only
when the blood carries them in excess. In diseased kidneys
the sensitive filtering membrane is damaged, and thus often
valuable elements are filtered out from the blood to the
detriment of the body.
Abel believes that possibly his false kidney, by which he
has filtered out red blood-cells, can be so perfected that the
blood of the human body might be forced to pass through
it, filtering out such poisons as, for example, corrosive sub-
limate, which the kidneys themselves cannot remove, and
other poisons which because of temporary kidney breakdown
cannot be eliminated.
16
The little fleas which us do tease
Have other fleas to bite 'em,
And these in turn have other fleas,
And so .... ad infinitum.
"Flea" is any animal that lives on or within the body of a
host and depends on that host for its food. All such are
parasites. Eccles claims that half of all the animals in the
world are parasites.
The most numerous and deadly parasites come from that
great half -animal, half-plant underworld known as bacteria.
Second only in deadliness are some of the unicellular organ-
isms of the animal world, the Protozoa. More annoying, but
of quite a different order in their powers of destruction, are
some of the lower members of the Metazoa subkingdom.
To the extent that parasites live on or within us or find a
temporary home with us, and to the extent that they are causes
186
THE PROCESSES OF LIVING AND THE GERMS OF DISEASE'
of disease and death, they are proper objects of our interest
and fit subjects for our attention. Indeed, the claim has been
made that natural death in man and higher animals is due to
parasitic organisms. This probably overstates the case, but
it is a fact that micro-organisms enormously influenced or-
ganic evolution, that certain forms are constant menaces, and
that no part, tissue, or function of our body is germ-proof.
The menace is great because of their astounding capacity to
multiply, constant because, like the poor, they are always with
us. A pin-scratch may be as fatal as a rifle ball; careless
handling of milk may plague a city.
The general problem of parasitism is complicated. We
shall look only at those parasites which are prone to infest
the human body and are likely to cause disease. What are
they, how are they carried, how do they enter our body, what
damage or disease do they cause, and how may we be rid of
them or acquire immunity? The answers to even these ques-
tions are often interrelated. Malaria, for example, is not a
bacterial disease, nor do we "catch" it — it is brought to us
by a mosquito. Malaria, as a disease, is not to be understood
without reference to its carrier and without a knowledge of
the life cycle of the germ which causes malaria. Again, rats
are not parasites, yet some of the deadliest scourges of the
human race are rat-flea-borne diseases. Why are the rats and
fleas immune to plague? And how do they carry germs? The
venom of a cobra, the ricin of the castor bean, the toxin of
diphtheria germs, are deadly. Are they related substances?
Only in their disruption of normal human processes of living
and in the similarity of the response our bodies make to
such substances.
It is true that no question can be raised regarding any one
phase of any human process of living without removing the
lid of all of life. The intricacy of life in its simplest forms is
profound enough; it is not simplified by the addition of para-
sites. And yet possibly all living processes in higher organ-
isms are brought about by aggregates of protein molecules
187
WHY WE BEHAVE LIKE HUMAN BEINGS
which function as micro-organisms. If we only knew more
about the protein molecule!
We shall, for keen minds are on its trail, and sooner or
later it will yield its secret and life will be new again.
Meanwhile, there are mosquitoes to swat. And with them
we may begin to call the roll of our parasitic enemies. Mos-
quitoes belong to Hexapoda (six-footed) insects, the most
diversified, the most numerous, and for their size the smartest
of all animals. Lice, fleas, ticks, bedbugs, jiggers, mosqui-
toes, flies — dozens of kinds, millions of each. And a variety
for every plant and animal on earth big enough to carry one.
They live on us, they live off" us. They give us nothing useful.
They irritate us. But they do not kill us. We are accustomed
to them, "adapted," immune.
That is what immunity means. We are not exempt from
fleas or dozens of other parasites. Only immune. We can
stand them. The germ of death or disease carried by a para-
site is another matter. Immunity may come in many forms.
Insects are the highest animals which infest or bedevil the
human body. Lower in the scale is a flatworm, the long, flat
Taenia, or tapeworm. Its life history is longer and not at
all flat. Man gets it from unsalted, uncooked pork. In his
alimentary canal it loses most of its anatomy and becomes
head and long body of dozens of segments, each for breeding
purposes a complete male and female. That is what it is, a
series of reproductive units. It needs no sense organs, has
none; as it feeds on predigested food it needs no digestive
apparatus, has none. Its head is a hook to hang on by and
a siphon to suck up food.
Our next lower animal parasitic enemies are the two
threadworms — ^hookworm, trichina. The trichina is well un-
derstood and now under control; we hear little of it. The
hookworm is well understood; but people will go barefooted.
The trichina lives coiled up in its cyst within a muscle cell
— rat, cat, dog, pig, man. There may be 80,000 cysts in one
ounce of ham: half males, half females. Eaten by man,
188
THE PROCESSES OF LIVING AND THE GERMS OF DISEASE
the cysts dissolve in the gastric juice, the worms are free.
They mate. One female produces 1,000 young. The young
break through and settle down in muscle cells — 100,000,000
of them in one dead man.
Hookworm continues to claim its millions of victims each
year simply because proper precautions are not taken to break
the vicious circle of its life cycle. It is another case of
Parasites Lost and Parasites Regained, in the words of a
Fijian school boy who, according to Dr. Vincent, had heard
about hookworms and Milton the same day. Hookworm eggs
hatch in warm, moist soil. The tiny worms enter the skin of
the bare feet, are carried by the blood to the lungs, where they
bore through into the throat, and thence are borne to the ali-
mentary canal, where 500 or more live parasitic lives attached
to the wall of the small intestine. Their millions of eggs are
returned to the soil to begin other cycles.
Lowest of real animals to infest us are certain unicellular
Protozoa. One group, the Sporozoa, is exclusively parasitic;
and all are internal, hence often called endoparasites. Some
abide in the liver, some in the intestine, some in the muscles,
some in the blood of their host. Some are deadly enemies
of the human race. Only bacteria are more widely distributed
and few germs have more plagued the human race than the
Sporozoan Plasmodia which cause malaria. Of the Sarco-
dina Protozoa, only the endameba is a real parasitic enemy
and in the tropics fairly destructive by causing dysentery.
A similar but smaller ameba makes its home in our mouth
and is always found in pyorrhea (pus-flow) lesions, though
it is not yet certain that it causes pyorrhea. Only one genus
of Infusoria is parasitic for man, causing diarrhea and dysen-
tery. Of the fourth Protozoan group, the Mastigophora, only
the Trypanosomas are parasitic — and cause the deadly sleep-
ing-sickness and allied diseases.
Below the lowest animals and below the lowest plants is that
half -plant, half -animal underworld of bacteria. But before
we turn to them, let us see how certain germs are carried by
189
WHY WE BEHAVE LIKE HUMAN BEJNGS
animals — flies, fleas, rats, etc. Incidentally, we shall see into
the breeding habits of certain germs.
The Black Death of 1348-49 devastated a quarter of
Europe, killed 25,000,000 people, and drove Boccaccio out-
side the v/alls of Florence, where he whiled away the time
writing the Decameron. In India, the pest bacillus cost
6,000,000 lives in ten years. Almost all plague bacteria are
carried by animals, and are transmitted to man by fleas, lice,
mosquitoes, or other parasites.
A flea on a dying rat seeks a fresh victim, carrying the rat's
plague germs with it. Any man will do. The flea empties
its alimentary canal, then bites; the bite irritates the skin, the
man scratches it — thereby opening his first line of defense to
the enemy! The germs left behind by the flea can now get
into the blood. In the new host they begin to multiply. An-
other flea may carry this tainted blood to another human
victim.
More instructive is the propagation of malaria, or ague.
When science found out where the mosquito gets malaria and
why the astounding clock-like regularity of the paroxysms
which wrack the bones with chills and burn the body of the
victim with fever, a long stride was made in making this
world safe for human beings.
Malaria is caused by three (possibly by four) varieties
of Plasmodia of the unicellular Sporozoa. Sporozoa repro-
duce by spores, hence the name. Ordinarily, one cell or one
bacterium divides and becomes two. In reproduction by
spores, one divides into many tiny spores, each spore grows
to life size, and again divides into spores. Each kind of
Plasmodium has its own time rate of reproduction. The ague
paroxysm coincides with this reproductive cycle.
The true home of Plasmodia is human red blood-corpus-
cles. Within, they grow to maturity at the expense of the
corpuscle. They then begin to divide and become a mulberry-
shaped mass of small, glassy, ameboid spores. This mass
190
THE PROCESSES OF LIVING AND THE GERMS OF DISEASE
rends the corpuscle apart. The spores thus freed attach
themselves to other corpuscles and begin a new life cycle.
The rending of the corpucles releases their toxic wastes
into the blood-stream, hence the fever; their destruction of
the oxygen-carrying constituent of the blood results in anemia
— and pernicious at that, without quinine.
The estivo-autumnal or quotidian (daily) Plasmodium
completes its life cycle every twenty-four hours. Each cycle
releases from six to eight spores or new parasites. It is the
most pernicious of all forms of malaria. The tertian life
cycle is complete in forty-eight hours, at which time it is about
twice the size of a normal red blood-corpuscle; from twelve
to twenty-four spores are released; the chill occurs every other
day. The quartan variety breaks from the corpuscle at the
end of seventy-two hours, with eight spores and the attendant
paroxysm; the attacks are every third day.
In other words, once any one of the three varieties of
malaria germs has entered the blood-stream, it propagates
itself by spores and without sex, asexually. The existence of
its progeny is dependent simply on the supply of red blood-
corpuscles. But how does it get into the blood in the first
place?
Enter the Anopheles mosquito, of which there are several
varieties. They can generally be distinguished from mere
mosquitoes by their approach. A mere mosquito on land-
ing humps its back, but holds its body parallel to the surface
on which it lights; the Anopheles lands with its head down
and body straight out at an acute angle with the surface.
The mere mosquito drills with its head for lever; the Anoph-
eles pushes in its siphon with its entire body.
It siphons up the blood of an ague victim. Also minute
Plasmodia spores. These are killed in the digestive juice of
mere mosquitoes, but begin a sexual life cycle in the Anoph-
eles. In this phase of development the Anopheles is the
true, man the intermediate, host of the Plasmodia.
The spores, in the Anopheles, develop into males or
191
WHY WE BEHAVE LIKE HUMAN BEINGS
females. The males develop fine thread-like processes. One
of these enters a female spore, fertilizes it. The now "mar-
ried" spore enters the wall of the mosquito stomach, becomes
encysted, grows; the mosquito's stomach looks as though
covered with warts. The full-grown "wart" now breaks up
into spores, each of which produces myriads of minute
thread-like bodies. These are carried to all parts of the
mosquito's body, even 10,000 in its salivary glands.
The mosquito bites a human victim, discharging saliva and
a few thousand thread-like spores. In man's blood they can
take care of themselves. They enter an asexual cycle. They
soon become incredibly numerous. Assume that the mosquito
left only 1,000 spores: by the tenth day they have become
100,000,000; two days later, 1,000,000,000. When 150,-
000,000 blood-corpuscles have been invaded, fever begins.
There may be double, even triple, infections — ^from suc-
cessive infections of the same type or from infections of
two or more types. Quartan fever, for example, may be
simple, double, or triple. In severe infections there may be
more Plasmodia than there are red blood-cells.
The germs of trench and typhus fevers are carried by
"cooties." Typhus fever alone killed 120,000 Serbians dur-
ing the war — all inoculated by lice. Wlien control measures
were inaugurated, the fever disappeared. But true control
cannot come to stay until the facts of propagation are known.
In 1915 there were 2,500 cases of malaria in an Arkansas
town; within three years there were 73: reduction of 97 per
cent. Formerly, yellow fever lived in the tropics and now
and then visited our Southern ports, with great loss of life.
It is almost forgotten now. Controlled by controlling its
mosquito carrier. In December, 1918, control measures
began in Guayaquil, Ecuador, with 88 cases; they fell by
months: 85, 43, 17, 2, 0. None since.
But many kinds of germs need no lower animal agency
to help complete their vicious life cycle; mere human social
relations suffice. The very manner of our living is sometimes
192
THE PROCESSES OF LIVING AND THE GERMS OF DISEASE
a factor in the presence of germs — and in our susceptibility
to their ravages. As Jordan says, tuberculosis is primarily
and chiefly a disease of men living in houses and of cattle
kept in stables. A tubercular patient may expectorate up to
3,000,000,000 tubercle bacilli in one day; the dried sputum
in a cool, dark corner may contain virulent germs for eight
months. A few drops of urine may contain up to 500,-
000,000 typhoid bacilli.
The typhoid bacillus, for example, before death overtakes
its host, passes into the body of another victim, carried by
milk, water, food, fingers, filth, flies. If it passes the acid
stomach of the new host, it has a clear field ahead until it
reaches the lymph-nodes of Peyer in the small intestine.
Whether it kills and so dies with its host, or is killed by the
leukocytes in the blood, it has already multiplied into an
army and has already sent some of its forces out to find new
victims. The germs of dysentery, cholera, etc., of the ali-
mentary canal, have similar cycles. But they must all be
carried; they no more "pass" from one victim to another
without a carrier than a letter crosses the sea without a carrier.
Many disease-producing germs which make their homes in
our nose, throat, or lungs (germs of tuberculosis, diphtheria,
pneumonia, scarlet fever, influenza, measles, whooping-cough,
pneumonic plague, etc.), may be carried by the air itself, and
generally are sneezed or coughed out to be wafted about
until they find new hosts.
During the Spanish War there was a case of typhoid for
every seven American troops, a death for every 71; in the
World War, there was one death for every 25,000 American
troops. In the old pre-antiseptic days, childbed fever mowed
down motherhood and in many hospitals regularly killed
practically all mothers. Death from childbed fever is now a
dark stain on a hospital's reputation. Deaths from typhoid
are still too common.
The conquest of germ diseases has only just begun. But
the start of that conquest might have been delayed until the
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WHY WE BEHAVE LIKE HUMAN BEINGS
sweet by-and-by without the discovery of the germs them-
selves under the microscope.
17
In 1683 there lived a curious Dutchman who ground lenses.
He scraped some tartar from his teeth, mixed it with water,
and examined it under his lens. What he saw was a more
astounding sight than that which confronted Balboa, who,
from his peak in Darien, saw a lot of water. For ages man
had known of the Pacific Ocean and millions of men had
sailed its deeps; Leeuwenhoek, the Delft lens-maker, was the
first human being to see a bacterium.
And the world promptly forgot him and continued for a
century and a half to argue "spontaneous generation" and
to exorcise devils as causes of disease. It remained for
Louis Pasteur (1822-95) to prove the part bacteria play in
decay, putrefaction, fermentation, and many other processes
until then hidden from the ken of man. Koch, in 1876,
proved the causal relation between the bacillus anthracis and
the disease anthrax, and in 1882 invented the "solid culture-
media" for the study of bacteria. Pasteur founded a new
science — biology; Koch revolutionized man's attitude toward
the world and gave the human race its first rational theory
of disease.
The naming of bacteria is still haphazard and much con-
fusion prevails. But bacteriology is a new science, its inherent
difficulties have been great, its progress marvelous beyond
conception to the surgeons of Napoleon's armies, who as-
sumed that pus was the first and necessary step toward recov-
ery from a wound. Some bacteria bear the name of their
host, some the name of their discoverer, some the name of
the disease they cause. Some bear all the traffic allows — for
example, Granulobacillus saccharo-butyricus mobilis non-
liquefaciens.
All bacteria show a fairly definite character and are either
194
THE PROCESSES OF LIVING AND THE GERMS OF DISEASE
pathogenic (disease-producing), zymogenic (ferment-produc-
ing), saprophitic (decay-producing), or chromogenic (color-
producing). But the line between bacteria which cause
disease and those which do not is far from sharp. Many
variable factors determine which bacteria are pathogenic,
when they are pathogenic, and for whom.
Bacteria are so small that almost nothing of their anatomy
is known but their shape, and that changes according to
circumstances. They not only vary during their life cycle,
but as individuals; even abnormal and monstrous forms are
found.
According to Jordan, all bacteria are inclosed within a
cell wall or capsule, which looms up under the microscope
like a halo. As this capsule is not cellulose, bacteria are not
true plants. Which means nothing, for many sure plants are
more like true animals than they are like true plants. It is
in the nature of living beings that there can be no sharp line
between the lowest plants and animals.
According to outline, three forms of bacteria are recog-
nized: rod-shaped, bacillus; corkscrew-shaped, spirillum;
round-like-a-berry, coccus. But these names give no clue to
their character; noxious and innoxious bacteria are equally
indifferent to how they look under the microscope. The cocci
are also called micrococci (small berries). Some cocci
divide in one plane and go in pairs like Damon and Pythias,
or form chains, and are called streptococci; some divide in
two planes and form flat sheets or clusters like a bunch of
grapes, and are called staphylococci; some divide in three
planes and form cubical bundles, and are called sarcinae.
There are also strepto-bacteria, traveling like chain-gangs.
But bacilli and spirilla divide at right angles to their long
axes and generally lead detached lives. Up to 1900 there had
been identified and named 1,272 genera of bacteria, divided
as follows: bacilli, 833; cocci, 343; spirilla, 96.
Because rather sharply differing from both bacilli and
cocci, Jordan believes the spirilla group should be put into
195
WHY WE BEHAVE LIKE HUMAN BEINGS
a class by themselves and called spirochetes (coil-bristle).
They are long, spiral, and thread-like; some ten times the
length of a red blood-cell. To this group belong the germs
of syphilis (treponema pallidum), yellow fever (leptospira
icteroides), yaws, infectious jaundice, and relapsing fever.
The average bacterium is about 1 /20,000 of an inch long.
The influenza bacillus is about half that size; the germ of
infantile paralysis is smaller yet. One hundred thousand
typhoid bacilli could lie snug in the space of a match; 15,-
000,000,000,000 of them to the ounce! A red blood-cell is
pretty small, but it is as big as a pea when magnified by the
diameters necessary to raise an influenza germ to the size
of a needle-point. The smallest visible bacterium is 18/100,-
000,000 of an inch in diameter; the ultramicroscopic or
filterable bacteria (viruses) are one-tenth that size; that is,
they are only half the shortest wave-length of any visible
light-ray. Under the ultramicroscope, such objects may be
seen, but merely as luminous points without diff'erence as to
size, shape, or structure. About forty filterable viruses are
known to exist, but nothing is known of the germs themselves
except that they pass through filters and can be very destruc-
tive. Among them are, presumably, the germs of smallpox,
dengue fever, trachoma, infantile paralysis, measles, hy-
drophobia, influenza, and foot-and-mouth disease.
All bacteria have some power of locomotion. The typhoid
bacillus can make about a tenth of an inch an hour, or 2,000
times its own length. Some travel faster — so fast that if we
could move as fast in proportion to our size, we could run a
mile a minute.
Bacteria show amazing vital capacity. They can defy
hours of boiling water; their spores can resist a temperature
of 212 degrees. Some sulphur bacteria haunt hot springs in
water at 190 degrees. Some multiply at freezing point. Ty-
phoid and diphtheria germs will live for days in a tempera-
ture of liquid air (284 below zero). Some bacteria have
196
THE PROCESSES OF LIVING AND THE GERMS OF DISEASE
been known to defy liquid hydrogen temperature (464 below
zero).
Even more astounding is their capacity to multiply. One
becomes two by simple division. The germ of Asiatic cholera
can divide every fifteen minutes. Within twenty-four hours
one could become 78,700,000,000,000,000,000,000,000,-
000; but the victim is usually dead in less than twelve hours,
killed by the toxins of these prodigious workers. In grow-
ing and dividing, they have consumed food and liberated
carbon dioxide. They are foreigners in our system, living at
our expense and leaving their toxic garbage for us to elim-
inate.
The air we breathe and the food we eat are full of bacteria,
and our body is covered with them. This is not literally true,
but it is true enough to emphasize the question : why are they
not always and more promptly fatal? Many factors enter into
the case. For example, an entire group of bacteria live on
our skin, where they are harmless. A scratch or a pinprick
opens the skin. Now they are inside our body, but the only
damage may be a boil or a pimple. Boils are usually not
contagious and rarely fatal. Sometimes they are. It de-
pends.
The hay bacillus is everywhere; in the air, water, soil;
probably some in the dust which my eyelids keep wiping from
my eyes. If I am in a weakened or run-down condition, this
bacillus may lead to a serious infection in my eye. Ordina-
rily, nothing happens. The hay bacillus is a parasite, at
home wherever it lands; it has established equilibrium with
its host. As Jordan says, the less completely adapted the
bacterium is to its host, the more virulent the disease. Old
diseases decrease in severity, increase in frequency.
Hence the really dangerous pathogenic bacteria as a rule
do their damage in short time; they are not adapted to live
in their host; they kill. To kill the hand that feeds one is
not biologic adaptation. How and why bacteria injure us
are again dependent on many factors. But we may recognize
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WHY WE BEHAVE LIKE HUMAN BEINGS
two general ways: by specific toxins locally released (tox-
emia); by invasion of blood-stream or tissue and resultant
damage due to general bacterial activity (bacteremia).
Diphtheria and tetanus are good examples of toxemic dis-
eases. They are localized; the toxin liberated is specific
and highly poisonous. Syphilis is a good example of a blood-
poisoning disease; at first localized, the germs soon enter the
blood-stream and from the blood may affect different tissues
or organs. Pneumonia and typhoid are tissue diseases pri-
marily, but the bacteria are present in the blood also. Sep-
ticemia may be due to other causes than the invasion of the
blood by the bacteria of suppuration.
What is toxin — for man or bacterium? In the body of a
man or an ape the bacillus of leprosy finds food and raiment;
in the body of a dog or a cat, a tomb. An anthrax bacillus
will not grow in a solution of corrosive sublimate stronger
than one part to 300,000; it will not live if the solution is
one to 1,000. As for bacterial poisons, the only general state-
ment that can be made is that they are very poisonous.
Tetanus toxin is 16 times more fatal than cobra venom, 120
times more fatal than strychnine. To put it another way,
the minimal fatal dose of strychnine is thirty milligrams; of
tetanus toxin, one-fourth of a milligram.
Certain plant toxins show resemblance to bacterial toxins.
One gram of ricin (from the castor bean), properly diluted,
contains lethal doses for one and one-half million guinea-
pigs. Ricin agglutinates their red blood-cells; but first there
is a period of "incubation" for the ricin, and an antibody
(antiricin) is formed. Such chemical behavior and physical
action of ricin are strikingly like those of bacteria. But this
gives us no clue to the chemical structure of bacterial toxins.
They are collodial, presumably, and in many respects suggest
enzymes in their action. In the fact that they do evoke anti-
bodies (antitoxins) lies most of the secret of tlieir control up
to the present time.
Which brings us up to immunity. But note, first, that there
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THE PROCESS OF LIVING AND THE GERMS OF DISEASE
are many kinds of immunity — and back of all the same
principle: I am either immune or I am not. If I take it or
catch it, I am not immune; if I do not take it or catch it, I
am immune. But I may go down with it to-morrow! In other
words, there are variable factors which will determine my
predisposition to infection or my power of resistance against
infection: age, hunger, thirst, fatigue, exposure to extremes
of heat and cold, are such variable factors.
Even different strains of bacteria vary in their intensity:
diphtheria and influenza, for example. There are mild epi-
demics, there are severe epidemics. Again, certain diseases
seem to predispose toward invasion by the germs of other
diseases. Acute tuberculosis may follow on the heels of
measles; streptococci may invade lungs already occupied
by tubercular bacilli. Typhoid fever and pneumonia, diph-
theria and scarlet fever, syphilis and gonorrhea, are well
known combinations of diseases.
Trypanosoma, the germ of sleeping-sickness, is carried by
flies from animal to animal. The disease is almost regularly
fatal; it cost Uganda 200,000 human lives, the Congo Basin
500,000. One infected animal sent to the Transvaal started
an epidemic among the cattle; 15,000 died.
Why any animals left, then; or any flies? The tsetse fly
which carries the trypanosoma is immune, as are the wild
animals which live in Central Africa. But let an outsider —
dog, horse, man — venture in! Outsiders are not immune;
their blood has no answer to sleeping-sickness; they die, un-
less they can get Bayer's "205."
So it was with Texas fever: the new cattle died. So it was
when whites introduced such "simple" children's diseases
as measles, croup, whooping-cough, to South Sea Islanders
and to American Indians. They were not immune. Their
bodies had not yet learned the art of compounding anti-toxins
to new toxins. They died — "like flies."
Which means that immunity itself is a relative term. We
are all susceptible under certain conditions ; we all have more
199
WHY WE BEHAVE LIKE HUMAN BEINGS
or less power of resistance. To some bacteria we are natu-
rally immune; to others we are naturally susceptible. The
problem is to acquire immunity. How can we get exemption
from disease?
By having smallpox we acquire immunity from smallpox;
also by vaccination. Against typhoid, from plague and
Asiatic cholera, we acquire immunity by vaccination with
dead bacteria — "cultures." With a secretion (or excretion)
of living bacteria we acquire immunity from diphtheria. In
other words, we become actively immune by incorporating into
our body "live virulent bacteria, less virulent bacteria, dead
bacteria, bacterial secretions, or bacterial products from
broken-down dead bacteria." An anti-bacterial serum is a
protective; an antitoxic serum is a curative.
Much is known of the "how" of immunity, almost nothing
of the "why." But great advance in the future will come from
specific artificial remedies — drugs, chemotherapy. The prob-
lem is to find a drug that will kill the bug but not the patient
— "magic bullets charmed to fly straight to a specific objec-
tive, turning aside from anything else in its path."
Quinine is specific death for malaria germs; ipecacuanha
for the ameba which causes amebic dysentery. Possibly
chaulmoogra oil is a specific cure for leprosy; asphenamin
("606"), for syphilis, relapsing fever, and yaws; atoxyl, for
sleeping sickness. The list of specific cures is pitiably small
yet. Bacteriology is new, immunology is newer. Only re-
cently have the chemotherapists had real targets to shoot at.
The problems which confront them to-day are vastly more
important than the puny worlds Alexander exhausted in his
conquests.
200
CHAPTER IV
THE ENDOCRINE GLANDS AND THE CAUSES OF DEATH
1. Endocrine Glands and Hormones. 2. The Thyroid Gland. 3. The Para-
thyroid and Thymus Glands. 4. The Adrenal Glands. 5. The Emergency
Functions of the Adrenals. 6. The Pituitary and Pineal Glands. 7. The
Pancreas — and Other "Sweetbreads." 8. Introducing the Gonads. 9. The
Dual Role of the Gonads. 10. The Female Gonads. 11. The Male Gonads.
12. Secondary Sexual Characters. 13. The More "Human" Sex. 14. Endocrine
Facts and Fancies. 15. The Individual That Is Regulated. 16. "How Can a
Man Be Born When He Is Old?" 17. One Good Defect Deserves Another.
18. The Parts That Wear Out First. 19. The Best Life Insurance. 20. Our
Total Mileage.
1
While life remains in the body, the duct glands furnish
the necessary chemicals for heat and energy metabolism and
for the preparation of materials for growth and repair. If
they fail to supply fuel, the body dies; if they fail to furnish
building material, the body stops growing. Let us assume
that the duct glands do not fail. It then appears that the body
which began as a fertilized ovum develops into a 9-pound
infant in 9 months. Why does it not develop into a 90-pound
child in 90 months, or a 900-pound prodigy in 900 months?
Even if it only kept up its first two years' rate-growth, it would
weigh 500 pounds in twenty-four years. It does not grow so
big. It stops. Sometimes too soon — it is dwarfed; sometimes
not soon enough — it is gigantic, though rarely, if ever, sur-
passing the nine feet three inches of Machnow, the Russian.
But it stops. Why?
Meanwhile the growing body keeps changing in size, shape,
proportions. Certain parts or organs appear before others
start to appear. For a while the brain grows faster than the
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WHY WE BEHAVE LIKE HUMAN BEINGS
motor mechanism; at other times the motor mechanism grows
more rapidly. The teeth have their special periods for
growth. The infant's thigh bone at birth has 2,000,000
bone-building cells. When that bone is a finished adult
product it contains over 150,000,000 bone cells. Why stop
at so few? How do the leg bones know when to stop growing
longer, the skull bones to stop growing larger? Why does the
body grow by fits and starts and finally seem to be complete?
What regulates the growth of all these parts and of the body
as a whole?
Moore replaced a rat's ovaries with the sex glands from
a male; her body and behavior took on decided male charac-
ters. By the same operation which converts the unruly bull
into a docile ox and the stringy cock into a tender-fleshed
capon, the Sistine Chapel in Rome up to 1878 maintained its
male sopranos. Why does the boy's voice begin to crack
and his face, almost overnight as it were, begin to grow a
beard where there was no sign of one? Is sex also, like growth
and individuality, a whim of "heredity," or are our sex, in-
dividual traits, and physical growth under the control of
definite regulators? Fifty years from now we shall begin to
know the details, but enough is now known of the ductless
glands and their secretions to open up not only a new chapter
of life, but new accounts with life. They regulate sex, rate
of growth of tissues and organs, and consequently physical
traits.
The secretions of the ductless glands are discharged direct
into the blood, hence they are also called glands of internal
secretion, or endocrines (endon, within; krino, I separate).
There are commonly said to be seven endocrines proper: thy-
roid, parathyroid, and thymus, in the neck; pituitary and
pineal, in the center of the head ; adrenals and spleen, in the
abdomen. But it is not yet proved that the thymus, pineal,
and spleen are true glands. The liver, pancreas, and sex
glands also function as endocrines.
Endocrine secretions are chemical in nature and are usu-
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THE ENDOCRINE GLANDS AND THE CAUSES OF DEATH
ally called hormones (exciters). They are also called auta-
coid substances: from acos, a remedy — they act like drugs.
They are drugs, some of them of astounding potency. In
fact, no man-made drugs are so powerful as some we make
in our own drug-store glands.
Mere regulation is not, of course, confined to the secretions
of glands. For example, the chief regulator of the respira-
tory system is carbon dioxide, given off by every cell of our
body; thus liberated, it functions as a hormone or "exciter."
But, as Abel puts it, the hormones actually known are definite
and specifically acting indispensable chemical products which
modify development and growth of other organs, especially
during embryonic life, and the entire metabolism, including
that of the nervous system, during adult life. Then, too,
there is a collective operation of the endocrines, as yet not
definitely known, but summarized by Barker as follows:
More and more we are forced to realize that the general form
and the external appearance of the human body depends to a
large extent upon their functioning. Our stature, the kinds of
faces we have, the length of our arms and legs, the shape of the
pelvis, the color and consistency of our integument, the quantity
and regional location of our fat, the amount and distribution of
hair on our bodies, the tonicity of our muscles, the sound of the
voice and the size of the larynx, the emotions to which our "ex-
terieur" gives expression — all are to a certain extent conditioned
by the productivity of our hormonopoietic glands. We are, in a
sense, the beneficiaries and the victims of the chemical correlations
of our endocrine organs.
In short, as the discovery of enzymes and antibodies gave
a new insight into the problem of the nature of living proc-
esses, the discovery of the hormones opens up anew the whole
conception of heredity. We can now say that men are alike
because they inherit the same kind of blood and similar sets
of glands to secrete hormones for the blood to carry; but that
men differ because they do not meet the same physical and
chemical conditions during life and as a consequence do not
203
WHY WE BEHAVE LIKE HUMAN BEINGS
develop the same catalyzers, the same immunity agents, or
the same regulating agents.
Or we can say, with Loeb, that the organism itself molds
itself into an organic whole; in the case of the human ovum,
into a human being, because the genus Homo and species
sapiens inhere in the specific protein of the human ovum; but
that the traits of individuality or "Mendelian characters" are
determined by the enzymes regulating metabolism and the
hormones in control of growth and so of personality.
2
The endocrine gland best understood is the thyroid (shield-
like) astride our Adam's apple. It varies individually and
with age. It is relatively largest in fetal life. At birth its
weight in proportion to the entire body is as 1 to 300, by the
third week as 1 to 1,160, and in the adult as 1 to 1,800.
It is generally larger in women than in men. Why this is so
is not yet known.
The thyroid usually consists of two equally developed lobes
two inches long, an inch and a quarter broad. They vary
greatly; one lobe may be much larger than the other, or may
be quite absent. Generally the two lobes are connected
by an isthmus; this also varies in position or may be absent.
There may be accessory thyroids down the trachea as far
as the heart.
Only in higher fishes does the thyroid become a ductless
gland, take on new functions, and start a new career. In
man, a duct is sometimes found in the isthmus — vestige of
a condition found in lowest fishes, echo of millions of years
ago. It is prone to trouble.
Frogs' eggs develop into fish-like tadpoles. Tadpoles lose
their tails and gills, develop true lungs, and become frogs.
Remove the tadpole's thyroid: it never becomes a frog; it
remains a tadpole for life. Feed a tadpole with thyroid: it
becomes frog in a hurry, the fish stage of its existence being
204
THE ENDOCRINE GLANDS AND TIJE CAUSES OF DEATH
reduced from a year to two weeks; but the frog is only as big
as a fly. Feeding thyroid to tadpoles evidently produces two
results: it hastens metamorphosis but retards growth.
Children with deficient thyroids, through removal, atrophy,
or injury, become heavy-featured, gibbering, idiotic dwarfs
known as cretins; they do not metamorphose into normal
adults. Their skin is dry and hairless; their sex glands are
under-developed; their pubic hair and puberty develop late
or not at all; their temperature is subnormal; they are pot-
bellied because their pelvis remains small, their limbs short
and thick. The corresponding adult condition is known as
myxedema: white, hairless, and thick, dry, rough skin;
obesity; lowered temperature and metabolism; pulse slow
and weak; mind dull.
These appalling results in both children and adults have
been corrected by feeding thyroid extract. The changes thus
produced have been little short of miraculous. Cretins have
increased in stature several inches in one year. The first
myxedema patient to be treated died in 1920 after twenty-
nine years of good health due to thyroid feeding.
Enlargement of the thyroid from whatsoever cause is called
goiter, or Derbyshire neck. But an over-developed or over-
active thyroid produces a definite disease known as toxic or
exopthalmic goiter, or Graves' disease. This is characterized
by increased metabolism and blood pressure, rapid pulse,
lax and moist skin, nervousness, and protruding eyeballs —
hence the name, "exopthalmic." The remedy is still in the
hands of the surgeon. The cause and significance of change
in the thyroid in toxic goiter and the cause of endemic goiter
are not yet understood. Nor is it understood why women are
more prone to toxic goiter than men, the disproportion in
some localities being as high as fifteen to one.
It is believed that the activating principle of the thyroid
hormone is thyroxin, isolated by Kendall in 1918. Thyroxin
is a crystalline compound of three molecules of iodine fixed
205
WHY WE BEHAVE LIKE HUMAN BEINGS
in a protein derivative : tri-iodo-tri-hydro-oxyindole propionic
acid, or 65 per cent of iodine.
Only the thyroid secretes thyroxin, and apparently it is the
iodine in thyroxin that tells the story. Iodine is found in
many seaweeds; is three times more abundant in codfish than
in human beings; is found in traces in milk and in drinking
water; and gets its name from its violet (iodes) color!
Possibly no life exists without iodine. Certainly normal
human life is impossible without one one-hundredth of a grain
of thyroxin a day. Three and a half grains of thyroxin are
all that stands between intelligence and imbecility. But,
there are, of course, dozens of causes of subnormal mentality
other than hypothyroidism.
No limit of function can yet be assigned to any one en-
docrine, because they are parts of an organic whole and func-
tion as parts of living individuals. So with the thyroid:
much is known, its whole story is far from known. But
from what is known Hoskins characterizes it as a regulator
of energy discharge to aid in adapting the animal to its en-
vironment. To Carlson it is a specific necessity for the
development of the reproductive mechanism in males and
for the lunar cycle in adult females. Both views are founded
in facts and are not in conflict.
3
Closely associated with the thyroid are two other endocrines
which develop in the epithelium of an embryonic branchial
cleft or gill-arch. Of these the parathyroids are so closely
associated in post-natal life in some animals that it is impos-
sible to remove the thyroids without removing the parathy-
roids also. They were only discovered in 1880.
They are about as big as peas and are paired, generally two
on each side and near the thyroids. They also vary in num-
ber, size, and position; they may extend far down the trachea.
Their function is not yet understood, nor is it yet known if
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THE ENDOCRINE GLANDS AND THE CAUSES OF DEATH
they are glands of internal secretion. It is known that death
follows their removal, generally in from twelve to forty-eight
hours. Sometimes recovery seems assured, but death has
only been postponed — and not beyond fourteen days. Death
is accompanied by tetany — acute muscular convulsions, and
not to be confounded with tetanus, or "lockjaw." In some
cases the hair and nails fall off, the teeth become loose and
shed, and cataract of the eye develops. Hence it is inferred
that they have to do with calcium metabolism. It is claimed
that tetany may be cured by parathyroid feeding, but Carl-
son maintains that true tetany has not yet been cured by this
method. Improvement may result from transplanting para-
thyroid from other animals, but when all the parathyroids
are removed tetany and death follow. Parathyroid function
is a condition of life.
What is tetany?
Infantile tetany is called "fits"; it is thought to be due to
defective parathyroids. The calcium metabolism is upset:
bad bone growth, the teeth do not calcify. The phosphate
metabolism also seems to be upset: not enough phosphates are
excreted. Also a tendency to acidosis in the blood, probably
due to defective carbohydrate metabolism. A substance called
methylguanidin appears in the urine and blood; it is bad
poison. Guanidin is also found in decomposing horseflesh,
in culture of the anthrax bacillus, etc.
Guanidin increases neuromuscular excitability: fits,
cramps, tetany spasms. A strychnine salt also does it. The
motor responses to stimuli are no longer co-ordinated, but
become convulsive — "tetanized." That is why the lockjaw
germ is called the bacillus of tetanus. With it at work releas-
ing its specific toxin, muscles of jaws and other skeletal
muscles "lock." Spasms follow the slightest stimulus. Possi-
bly methylguanidin breaks down the resistance of the synap-
ses of the neuromotor system — as strychnine and tetanus toxin
are supposed to.
We seem to be far from the parathyroids. It is not known
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WHY WE BEHAVE LIKE HUMAN BEINGS
if they secrete a hormone or if they are glands, but whatever
they are they are vital structures, and certain death — and
death with certain accompaniments — follows their removal.
But Collip has recently reported that he has prepared an
extract from animal parathyroids, which he calls parathyrin.
With this he claims to control tetany in dogs, and to have
treated a child in desperate condition with successful results.
No one knows yet what constitutes a normal human para-
thyroid. There is even more doubt as to what is a normal
thymus, or whether it is a gland, or what happens when it is
removed. It lies just under the upper end of the breast bone,
is well developed in the fetus, better developed at the age of
two, largest at puberty. It then begins to lose its character
and becomes connective tissue, lymphatic tissue, and fat. But
this change is delayed by castration. Hence it is assumed
to hold back the development of the sex glands until puberty.
Post-mortem examination of 400 idiots showed no thymus in
75 per cent. Its removal in young animals retards growth
but hastens sexual development ; the sex glands remain weak,
the body flabby and dwarfed.
Riddle claims that the thymus lost its value for man and
mammals when their ancestors began to incubate their eggs
within their body and ceased laying them, as do birds and
reptiles, with albumen and shells. That was the original
function of the thymus. Pigeons whose thymus has been re-
moved lay eggs without shells; but if fed thymus, will lay
normal eggs with shells. If your hens' eggs have .too little
albumen or a soft shell, feed your chickens dried thymus of
an ox. And thank the thymus because its secretions made it
possible for our reptilian ancestor to invent an egg that could
evolve into a human ovum.
4
The adrenals, or suprarenals, get their name from their
position just above the kidneys. Normally they are of the
208
THE ENDOCRINE GLANDS AND THE CAUSES OF DEATH
size and shape of a large bean. But they vary: one — or, in
rare cases, both — may be absent; there may be accessory
adrenals varying in size from a pin head to a large pea. Re-
moval of one adrenal produces no known result. Removal
of both is always fatal, often within a few hours. When
death does not follow their removal it is because accessory
adrenals are present and can function.
The adrenal in some fishes is two separate organs. In the
human embryo it begins as two; these unite to form one body
with two distinct parts: an outside cortex, or bark, and a
medulla, or core, completely inclosed by the cortex. The
cortex arises from the middle germ-layer and is derived from
the Wolffian body, which also assists in the development of
the urogenital system. The medulla is part of the outer germ-
layer and is derived from the same embryonic tissue as is the
autonomic nervous system; it is largely composed of nerve-
like tissue. Its importance is possibly second only to that of
the brain. No other organ in the body is so well supplied
with blood.
Removal of the cortex is always followed by profound
prostration, loss of appetite, apathy, labored respiration,
weak and irregular heart, paralysis, and, within a few hours
or days, death. Its secretion has not yet been isolated; it is
not certain whether it is a secreting or a detoxicating organ.
It is a vital organ. It appears to stimulate sex-gland growth
and bring on sexual maturity. Its over-activity, as, for ex-
ample, when involved in a tumor, makes for precocious sexual
development. Wlien it is infected, as it sometimes is in tuber-
culosis, a disease results called "Addison's," from its dis-
coverer in 1855. This is the only disease definitely known
to be caused by insufficient adrenal cortex. It is as yet in-
curable and ends in death. Nor has the attempt to overcome
cortical deficiency, due to disease or removal, yet met with
success. Addison's disease is accompanied by great muscular
weakness, nervous depression, digestive irritability, and such
209
WHY WE BEHAVE LIKE HUMAN BEINGS
increase in pigmentation of the skin that a white skin looks
like bronze.
The medulla of the adrenals is possibly more important
than the cortex. As it cannot be removed without injury to
the cortex, it is not yet certain that it is a vital organ as the
cortex is known to be. Adrenin, the hormone of the medulla,
was the first endocrine secretion to be isolated. Its deriva-
tive was discovered by Abel in 1897 and named "epine-
phrin" ; its pure form was isolated in 1901 by both Takamine
and Aldrich. By 1908 it was so well understood that it was
artifically produced from a coal-tar derivative. It is now a
drug on the market and sold as epinephrin or adrenalin.
Abel describes it as a di-hydroxymethyl-aminoethylol benzine
or an "aromatic amino alcohol." Here is its formula :
C6H3(OH)2COCH2Cl + NH2CH3 > C6H3(OH)2.COCH3.
NHCH3.HCI.
And here is a curious fact. This remarkable drug is found
in man in a gland of internal secretion. The principle of this
drug is the constituent of a gland of external secretion in the
skin of a toad. That fact was unknown to the New England
colonists, but Toad Ointment was known. Abel quotes the
recipe:
Good-sized live toads, 4 in number; put into boiling water and
cook very soft; then take them out and boil the water down to
half pint, and add fresh churned, unsalted butter, 1 pound, and
simmer together; at the last add tincture of arnica 2 ounces.
What was Toad Ointment good for? Sprains and rheuma-
tism! The Chinese still treat or "cure" dropsy with toad-
skin preparations, as did Europe up to 1775, when it was
supplanted by digitalis. But if the colonists had persevered
they might have isolated from their toads, as did Abel, a
crystal composed of C18H24O4 and called bufagin (bufo,
toad) with the property of a powerful heart stimulant and
thereby good for dropsy. But they could not have derived
epinephrin from their toads because they did not have die
210
THE ENDOCRINE GLANDS AND THE CAUSES OF DEATH
right kind of toads. Epinephrin is found in the skin glands
of external secretion of an Upper Amazon toad. The secre-
tion of these skin glands smeared on arrows makes a fine
poison for the natives, so powerful that in a few moments it
will kill a deer or a jaguar. The skin of that Amazon toad
contains both epinephrin and bufagin, both powerful drugs,
acting fatally on the heart and blood vessels. Imagine what
happens to the animal that eats that toad!
Which brings us back to adrenin, a powerful drug, a power-
ful cardio-vascular stimulant. Normally our blood contains
about eight milligrams of it, which means that the proportion
of adrenin to arterial blood is one part to a billion. Admin-
istered as one part in twenty million, it acts on the uterus and
is a useful drug in hemorrhages following delivery. It in-
fluences some tissues when diluted to one part in 100,000,-
000. It depresses the intestinal canal when diluted to one
part in 330,000,000! What such dilution means has been
worked out in terms of street sprinklers each of 625 gallons
capacity. A procession of such sprinklers twenty miles long
and 200 to the mile would hold just enough water to dilute
one ounce of adrenin down to one dose. Large doses are
fatal.
Adrenin is a drug, one of the most potent our body con-
cocts. Yet adrenal feeding leads to no known or proved re-
sults. The administration of the drug adrenalin does lead
to profound results. Our body blood contains this drug.
Whether it is made by or excreted by the adrenals is still an
open question, but that adrenin has specific action on the
vascular system, the nervous system, the blood, the alimentary
canal, and on sugar mobilization, there is no doubt. Nor
is there any doubt that when administered as a drug it in-
creases the action of local anesthetics by constricting the
blood vessels, thus preventing local loss of the anesthetic.
And as this reduces the amount of anesthetic required, it
also reduces the amount of toxin danger from the anesthetic.
It checks hemorrhages. It allays the spasms of acute bron-
211
WHY WE BEHAVE LIKE HUMAN BEINGS
chial asthma. It also stimulates weak hearts and fortifies the
hearts of the old and infirm against the shock of operation.
In short, adrenalin exerts an influence upon all smooth
muscle enervated by fibers of the autonomic nervous system.
That makes its responsibility enormous, its influence on hu-
man destiny second to none.
What, then, is the nature of this tiny but potent capsule
tucked away in the depths of the abdominal cavity, nestling
above the great excretory organs of the blood? Recall the
potency of a toad's bufagin to control the heart, the potency
of a toad's epinephrin to kill a strong animal. Try to picture
a molecule of human adrenin from the above formula.
Realize the close association of the fundamental vital proc-
esses with the autonomic system. Is the human adrenal a
"brain" which takes charge of us when we are confronted
by emergencies which mean life or death? It may be thought
of in that way.
5
In crises our body goes on a "war footing" — as our country
did a few years ago. Piano manufacturers began to make
airplanes. Artists turned from painting corset advertise-
ments to camouflaging battleships. Our sugar rations were
cut that the fighters might have enough. The entire plant of
the nation turned from peaceful pursuits to speed up the
fuel for the engines of war. Life had become a dog-fight.
Ever try to take a bone from a dog? Or observe a cat
when a dog suddenly appears? Or a mother when some one
injures her child? How do you feel when you are "horror-
stricken," "sick with disgust," "paralyzed with fear," "crazy
with pain," or so mad you "choke?" Tongue cleaving to
the roof of the mouth, "cold-sweat," pupils of the eyes dilated,
pounding heart, hurried breathing, hair on end, muscles of
face and especially of the lips trembling and twitching: such
are among the obvious symptoms of pain, of horror, of fear,
etc.
212
THE ENDOCRINE GLANDS AND THE CAUSES OF DEATH
We recognize many emotional states and are subject to them
in varying intensity: pain, anger, fear, rage, horror, sorrow,
anxiety, grief, terror, disgust. An insulting word may liter-
ally alter our entire nature. We feel these states ; we observe
the results in others. What is not so obvious is that the body
itself often undergoes profound physiological change.
The mechanism by which our natures can be suddenly
altered is to be found in the middle or sympathetic division
of the autonomic nervous system and — according to the
theory — the secretion of the medulla of the adrenal gland.
The way these two work together and the striking, sudden,
and far-reaching consequences of their actions, form the basis
for Cannon's claim in 1914 that adrenin is nature's reply to
the crises, the unexpected do-or-die emergencies of living
animals. Emotional behavior gets its kick from adrenin.
With adrenin cowards may fight for their lives, brave men
may surpass themselves, and all of us can run as we never
ran before; or shed tears of sorrow over the loss of friends.
There are three divisions of the autonomic nervous system.
The upper, or cranial, is concerned with the joys and sorrows
of life. Its nerves conserve the body, building up reserves
and fortifying the body for times of crises. By narrowing
the pupils they shield the eye from too much light. By slow-
ing the heartbeat they give the heart muscles longer periods
for rest. By causing the mouth to water they set the juice
flowing and supply muscular tone for the alimentary canal's
ceaseless movements. The lower, or sacral, division covers
the emptying mechanisms of large intestine and urogenital
system; relief and comfort acts.
Between cranial and sacral is the sympathetic division —
enormously important. It dilates the pupils of the eyes, hur-
ries up heartbeat, stands hairs on end by causing each smooth
hair-muscle to contract, opens sweat glands (pouring out
excess heat), stops movements in stomach and intestine, re-
leases sugar (the best fighting fuel) from the liver; and re-
leases adrenin. The medulla of the adrenal, alone of all the
213
WHY WE BEHAVE LIKE HUMAN BEINGS
endocrine glands, is connected with the autonomic nervous
system.
Here is the point. Adrenin itself, injected into the blood,
will dilate pupils, stand hairs on end, constrict blood vessels,
stop the vegetative activities in alimentary canal, and release
sugar from the liver. Remove the liver from the body, keep
it alive artificially: adrenin will cause it to release sugar.
The real business of the adrenal glands, according to Can-
non's theory, is emergency function. When we must fight or
run for our lives, our body has no time to fool with a mouth
watering for its appetite or several yards of alimentary canal
activity. The test tubes for chemical action, and the fires to
keep these actions going, must be neglected for the moment.
Their energy must be made available for action in the big
striped muscles of the motor fighting-or-fleeing mechanism.
When a joy is so strong or a sorrow or a disgust so deep
that it breaks over the threshold of the cranial division and
enters the sympathetic, we lose our appetite: no saliva, no
gastric or pancreatic juice, no movement in the intestine.
Even an empty stomach stops growling and holds its peace
when war is on.
And war is on when any of life's instinctive acts with
emotional trimmings are thwarted. Anger. The body is
prepared to fight. All its life long life has had to know how
to kill, how to avoid death. It has had to learn to count on
its muscles and its nerves when the test comes. Adrenin is
supposed to be the answer.
According to Cannon's theory, adrenin bucks us up. It
speeds up the heartbeat. Draws blood from spleen, kidneys,
intestines, and other inhibited organs of the abdomen — thus
also reducing their size. Drives blood to the skeletal muscles,
brain, and lungs. Relaxes the smooth muscles of the tiny
air sacs in the lungs, thus facilitating the exchange of carbon
dioxide waste for the greater oxygen required in great eff'ort.
Orders the liver to give the blood more sugar, the optimum
source of nmscle energy. Drives fatigue from the muscles.
214
THE ENDOCRINE GLANDS AND THE CAUSES OF DEATH
Contracts the blood vessels of the skin and makes the blood
coagulate more quickly, so lessening our liability of bleeding
to death in case of wound. Adrenin wins battles and makes
men brave; lack of it may make them cowards.
It has been urged against Cannon's hypothesis that it is not
yet conclusively proved. What is proved is that without
adrenals — or accessory adrenals — no man lives ; with adrenin
far-reaching changes occur which, combined, transform the
vegetation body into a fighting machine. Nor is there any
doubt as to what our emotions do to us. The role that Gannon
ascribes to the adrenals is reasonable and plausible; it has
proved to be a working hypothesis in biology.
6
The pituitary gland is about as big as the tip of the little
finger, hangs from the base of the brain by a hollow stem
(hence also called the hypophysis cerebri), and is housed in
a pocket of the sphenoid bone called the Turk's saddle. It
is as near the center of the head as it can get ; hence operation
on the pituitary is enormously difficult. But if the patient
— dog or man — does not die from brain injury, removal of
the pituitary itself is not fatal. It is not a vital organ, but a
normal pituitary is essential to normal life.
The gland has two lobes, each of different embryonic ori-
gin, and probably different in function. The anterior lobe
is much the larger and is an ectoderm structure, arising as
a fold of the lining of the mouth. Its structure is that of a
gland and it has a rich blood supply. It does not remain
constant in size. It seems to be associated with rate of growth
and sexual development. Its removal is followed by many
symptoms, but which are due to its removal, which to injuries
to the brain, is uncertain. A substance called tethelin pre-
pared from this lobe has been used experimentally and other-
wise, but no chemical individual has yet been isolated. It is
215
WHY WE BEHAVE LIKE HUMAN BEINGS
claimed, but not proved, that tethelin hurries sexual maturity
in the young and promotes sex activity in adults.
The posterior lobe arises from the floor of the third ven-
tricle of the brain and is largely nerve tissue. For a dozen
years its active principle was known to science and used as
an extract called pituitrin by physicians and surgeons,
especially as a rival to ergot in obstetrics. Used in overdoses
or at the wrong stage of childbirth, it caused several deaths,
because it can so act on the uterus as to tear it open.
Abel is convinced that the posterior lobe has only one
hormone and not four, as had been claimed by German
chemists. From it he has only recently isolated a pure tar-
trate which he characterizes as "extraordinarily potent" and
endowed with several different and distinct properties. It is
a thousand times more powerful than any hitherto known
stimulant for non-skeletal muscle tissue — a thousand times
more powerful than the "extract" pituitrin which, wrongly
used, could tear a uterus asunder!
Recall the twenty-mile procession of street sprinklers re-
quired to reduce an ounce of epinephrin to a test dose: to
reduce an equal amount of Abel's pituitary hormone would
require not twenty miles of sprinklers, but 5,000 miles! The
actual test was made on a virgin guinea-pig's uterus; it
contracted when suspended in a solution of one part hormone
to 18,750,000,000 parts water. Such facts, as Hoskins says,
make endocrinology kin to astronomy.
This hormone acts on the entire cardio-vascular apparatus.
By restricting the small blood vessels it causes prolonged rise
of blood pressure. It acts upon the respiration, causing a
rhythmic increase of breathing up to a certain degree of
rapidity, then a gradual decrease again to a temporary stop-
page of breathing.
When injected daily it has proved a remarkable remedy in
the disease known as diabetes insipidus, not to be confounded
with sugar or mellitus diabetes. In the latter the kidneys
eliminate sugar that belongs to the blood and is needed by
216
THE ENDOCRINE GLANDS AND THE CAUSES OF DEATH
the body. In insipidus, it is claimed the kidneys leave so
much sugar in the blood that the body gets fat. But the
danger in diabetes insipidus is the excessive and uncontroll-
able elimination of water by the kidneys and a consequent
incessant thirst.
"Joe," the fat boy of Pickwick Papers, had a fat chest,
flabby muscles, and sexual infantilism. To-day "Joe" would
be diagnosed as dystrophia adiposogenitalis. The anterior
lobe of his pituitary was probably diseased and consequently
under-functioned.
Too much activity in the anterior lobe in early life is
believed but not proved to lead to gigantism, in later life to
acromegaly. There seems to be no doubt that the pituitary
gland is closely related to growth, especially in connective
tissue, cartilage and bone, and sex-gland activity. But where
abnormal growth occurs it is rarely possible to say whether
it results from specific activity — too much or too little — in
the gland, or from the pressure of a tumor on or in the gland
or on the floor of the third ventricle of the brain. Other
glands than the pituitary may be involved when the pituitary
itself is abnormal. Whether the pituitary was the primary or
the secondary cause of the upset in response to growth stimuli
is not yet known.
Abnormal adult growth changes know^n as acromegaly are
characteristic and unmistakable: enlarged bones of the head,
hands, and feet, general lassitude, pains in the muscles, lack
of interest, and depressed sex activity often leading to im-
potence or amenorrhea.
The famous Irish giant Magrath had a pituitary as big as
a hen's egg. His hands resembled shoulders of mutton, his
lower jaw was a massive appendage to a huge face. A dis-
eased pituitary in a normal adult caused the face to grow
massive and ugly, with bulging masses about the eyes, the
nose huge, the lips thick; the chest huge and barrel-shaped;
the hands and feet of enormous size. A dwarf of twenty
years with an under-developed pituitary had the bones of a
217
WHY WE BEHAVE LIKE HUMAN BEINGS
child a few weeks old. Another dwarf of mature years and
so tiny as to have been "served" in a pie at the Duke of Buck-
ingham's table in honor of the Queen of Charles I, began a
second period of growth. Some alteration in the pituitary,
possibly.
That the pituitary is concerned in sex growth is inferred
from the fact that it becomes enlarged following castration;
as it also does during pregnancy when the ovaries temporarily
change their function. It is suggestive also that at that time
the hands sometimes enlarge and the face changes.
Perhaps no structure, in proportion to its size, is more inter-
esting or of less importance than our pineal gland. Of the
size of a grain of wheat, it lies high up in the base of the
brain behind and above the pituitary. It reaches full de-
velopment at the seventh year, then begins to atrophy, and
in adults has become connective tissue and "brain sand":
minute grains of phosphate and carbonate of lime. This
"sand" is often found elsewhere in the brain, even in fetal
life.
Descartes held that the pineal is the seat of the soul. He
was long on philosophy, but short on comparative anatomy.
Yet possibly he was nearer the truth than he realized.
Millions of years ago the pineal was a third eye and looked
straight up to heaven. Extinct reptiles have a hole in the
skull for this pineal eye. The sphenodon, an almost extinct
New Zealand reptile, is the only living animal with a pineal
organ that resembles a true eye. Most lizards have a pineal
organ, and, above, a hole in the roof of the skull. The hole
is covered by a scale; the organ, therefore, cannot function as
a true eye, it may serve as an organ for sensing lights and
shadows. Except the lowest fishes, all vertebrates have a
relic of this "eye." In Man the "relic" has a vestige of the
optic nerve.
No pineal hormone has yet been discovered, nor is it yet
certain that it is a gland. Nothing certain is known of its
function, nor is it certain that it has any importance beyond
218
THE ENDOCRINE GLANDS AND THE CAUSES OF DEATH
pre-adolescence, if it has any then. From the fact that tumors
of the pineal are often associated with precocious mental and
sexual development, it is inferred that its business is to pro-
mote early physical growth and retard sexual development.
But this is only inference — the tumor may also have involved
the mid-brain.
7
To Lavoisier's dictum: "Life is a chemical function," we
might add, "and ceases to function without sugar." At any
rate, we eat more sugar than we should, because our body
fmds sugar where we little suspect it. Sugar is the finest
fuel our blood can find to keep life on the move. When any-
thing happens to our sugar refinery, sugar storage, or sugar
delivery, we suffer from one of several more or less fatal
diseases.
The regulator of sugar metabolism is a group of secreting
organs known as the islands of Langerhans, in the "sweet-
breads" or pancreas, and which act as a gland of internal
secretion. Its hormone, insulin, is delivered direct to the
blood. Pancreatic juice, an important digestive fluid, is
delivered by the duct of Wirsung to the alimentary canal.
Diabetes (from the Greek "to go through") follows when
the islands of Langerhans stop functioning. The isolation of
insulin, chiefly due to Banting and McLeod, ends a search of
many long years and closes one of the most interesting chap-
ters in the new science of endocrines. There is a remedy for
diabetes mellitus, but no cure. Life can be prolonged "in-
definitely" ; but insulin feeding alone will not prevail without
control of diet.
It is significant that of the more than a million sufferers
from diabetes in this country 90 per cent are overweight;
and that of those over fifty years of age there are twenty fat
for every thin diabetic sufferer. From which we infer that
the human pancreas as regulator of sugar metabolism tends
219
WHY WE BEHAVE LIKE HUMAN BEINGS
to break down when we take on more fat than we require. We
take on fat when we eat more sugars and fats than we use up.
The pancreas is a very vital organ. Its removal, or the
removal of seven-eighths of it, is followed by a condition
like that of diabetes: increased urine, abnormal thirst and
hunger, death. Its hormone, delivered to the blood, regulates
the output of glycogen from the liver, and is necessary for
the building of glycogen and the oxidation of sugar by the
body tissues. This is the route:
The portal blood carries glucose to the liver. The liver
converts glucose into glycogen (animal starch). The liver
itself is not an endocrine gland, although it does deliver
sugar to the blood direct. It stores up no hormones, but it
reeks with extracts. It stores vitamins; it destroys fat; it
stores glycogen. It is a vital organ. Nothing takes its place
or can do its refining. All its processes depend upon its own
liver cells. How it converts sugar into animal starch for
storage purposes and how it reconverts it into sugar when
the secretion from the islands of Langerhans tells it to do
so, are not known. It does. If the islands stop sending
messages, the liver gives up all its sugar to the blood, but the
body cells cannot store or burn it and so it is filtered by the
kidneys from the blood and passed on to the bladder.
The spleen has no duct; it has no secretions. It is not a
gland. Just what it is no one knows. Its functions are not
specific, nor does its removal seem to impair health, growth,
or longevity. In the fetus it is probably an incubator for
red blood-cells; after birth it seems to be an incinerator of
red blood-cells. They work so hard carrying oxygen they
wear themselves out in from ten to fifteen days. Perhaps 10
per cent of all red blood-cells are destroyed each day. It is
possible that an "enlarged" spleen destroys red cells faster
than it should; it may therefore be responsible for chronic
anemia. It does produce a chemical catalyzer; its enzymes
convert nucleins into uric acid.
The secretions of the stomach and small intestine — gastrin
220
THE ENDOCRINE GLANDS AND THE CAUSES OF DEATH
and secretin — are drugs to be used on the spot. They are
dangerous drugs if used elsewhere in or on the body. Stomach
and intestine may produce hormones. May. If they do, they
presumably regulate the pancreas, gastric glands, etc.
Neither lymph nor lymph "gland" has any endocrine func-
tion. Nor has the blood. A quart of my blood may tide you
over until you can make enough to supply your loss. But
my blood is my blood; it is in dynamic equilibrium, con-
stantly changing to meet the specific requirements of the
particular families of cells on its route in my body.
Kidneys, if veal or sheep, are good to eat. They are good
as food. But "extract of kidney" is as good to repair a faulty
kidney, or to treat uremia or nephritis, as powdered glass is
to restore a watch crystal. The kidney is not a gland, it
secretes nothing. It is a filter or excretory organ.
Other "extracts" are doped out to meet the demand. Brains
for dementia praecox, tetanus, epilepsy, etc. Such treatment,
says Carlson, is "less rational than the principles and prac-
tices of Mrs. Eddy. Perhaps we could make for greater
progress if the manufacturers [of dried brains] could be
induced to use the brains of horses instead of asses and sheep
for their raw material, and the finished product was taken by
the doctor instead of being given to the patient."
Dried lungs, tonsils, retina, iris, nasal mucous membrane,
and such can be had in the drug stores; "cures" for tuber-
culosis, tonsilitis, etc. Rubbish. The few hormones that are
really known are so powerful, so useful, so wonderful, that
they have encouraged imitators. The result is a new crowd
of quacks, ready to "feed" anybody anything that sounds like
something and is therefore presumably a remedy.
8
Gonads is Greek for seeds. As the organs or glands of
reproduction of both sexes produce seeds, it is a convenient
and polite word for testes and ovaries. But the newspapers in
221
WHY WE BEHAVE LIKE HUMAN BEINGS
referring to gonad operations, rejuvenescence, etc., always
speak of "glands." Only the context makes it certain that
the "glands" referred to are not the parotid or thyroid or
some other equally "respectable" gland.
This reluctance — which Robinson characterizes as "shame-
faced, prudish, and squeamish" — to face the facts necessary
to solve some of the simple but vital problems of everyday
life is almost a chronic psychosis, with signs now and then of
a tendency to sanity.
Psychology has diagnosed the "impurity complex" and
shown us what is back of the blatant prude who advertises
his or her "purity." It has also shown that the purity of the
ignorant, when purchased at the price of a stifled natural
curiosity, is not a safe and sane "purity." The study of
biology has begun to break down this impurity complex and
the unholy, unnatural doctrine begun by early Christian
monks that the sex impulse is man's sign of degradation and
the source of his most devilish energy. Nature knows better.
Sex is a primary biologic function of all life above the
lowest. Its characters and qualities have an ancient lineage.
Its impulse is as real as is the force which makes the tides to
ebb and flow. It has profoundly influenced structure and
behavior. It is a fundamental element of all higher life; its
external characters a neat advertising dodge of Nature by
which she sells her wares and thereby insures her family.
To sex we owe more than poetry; we owe the song of birds,
all vocal music and the voice itself, the plumage that comes
to supreme glory in the bird of paradise, the mane of the
lion, the tresses of women, the blush of the maiden, the beard
of men, and all higher forms of life in plant and animal
world. It is woven into every fabric of human life and lays
its finger on every custom. To the debit side of the sex ac-
count we must charge many silly stupidities and some of die
foulest injustices which go to make the thing we call human
culture the amazing and variegated mosaic that it is.
We are more enlightened than we were, but we have not
222
THE ENDOCRINE GLANDS AND THE CAUSES OF DEATH
yet reached the stage where the mere mention of sex will not
provoke some one to respond with a reproach or an insult.
Whole blocks on Main Street assume that "sex knowledge"
is of questionable propriety, or, at best, to be kept dark in
"doctor-books"; or regard it as the banal possession of the
frankly shameless. As a result, most pseudo-scientific "sex"
literature slops over into the emotions and lets facts alone, or
presents facts under disguises. Much of it has no biologic
background or anything of the laws of life which govern
man no less than every living thing. It is fear (sometimes
called "reverence") that makes us "let sex alone." It is
mock modesty and foolish shame, masquerading under the
name "decency," that compels museums to clothe marble
Fauns and plaster Joves and bronze Cupids with plaster-of-
Paris fig leaves, often awry or nicked at the corner.
Back of much of this confusion and nonsense is the para-
dox which culminated in Puritanism: Marriage is a divine
institution and the god of Love is a saint, but sex is shameful
and Cupid is a carnal beast.
Man is "high," "animals" are "low" — without minds and
of course can have no "souls." We have. Ours is a
"divine" parentage, our bodies "sacred." Hence art, from
Phidian sculpture to sophomoric poem, tends to the greater
glory of Man: men and women more like gods and god-
desses; gods and goddesses glorified men and women.
And so it came about that the commonest thing in nature
next to keeping alive became invested with the sanctity of
heaven. Love begins with a capital "L" because it is sacred.
So it is. Without it the world of man stops. There would
be no more fishes in the sea if the males did not like the
females. Love is fine. Put it on a pedestal, magnify it,
glorify it, deify it. But why leave Cupid on the pedestal?
To worship him blindly is on a par with any other fetishism,
and quite as intelligent. Take him down and dust him off,
repair his broken ears, mend his battered nose, refeather his
223
WHY WE BEHAVE LIKE HUMAN BEINGS
arrows and restring his bow. Why not have a look at him?
What is he made of?
9
Certain glands are essential to life. Their removal is fol-
lowed by death. Not so the gonads proper. They may be
removed, in fact are constantly being removed — especially
those of women — in the operating rooms. What happens?
The patient lives. The gonads are not necessary for indi-
vidual life, only for that of the race or species.
Physical differences between men and women are sexual.
There are primary and secondary differences. The second-
ary characters begin to assume definite form in both sexes
at the beginning of puberty. These characters are by-
products of the male and female gonads.
The gonads are like true duct glands in that they discharge
their secretion through ducts, but this secretion, unlike that
of other duct glands, is not discharged into and consumed
by the parent body. The gonads have an additional func-
tion: they secrete a hormone which regulates the appearance
and growth of the secondary characters and supplies the
impulse back of sex behavior. In this they are like true
endocrines, which deliver their regulating secretions direct
to the blood stream. Thus the gonads are also glands of
internal secretion.
For ages it has been known that boys or girls deprived of
their gonads before puberty develop into "womanly" men or
"manly" women and throughout life retain an infantile type
of body. Eunuchs ("guardians of the couch," created for
religious and social ends), develop neither the voice nor the
beard of men; in women similarly altered the mammary
glands remain undeveloped, their bodies do not become so
feminine.
Experiments on chickens show that when the ovaries are
completely removed from a young hen, she begins to take
224
THE ENDOCRINE GLANDS AND THE CAUSES OF DEATH
on the secondary sexual characters of the male : she develops
comb, wattles, and spurs; her plumage becomes more bril-
liant; she grows larger; she takes on the typical behavior of
the rooster. This can only mean that the ovary itself, by its
own internal secretion taken up into the blood stream, has
power to modify the body in the direction of the female sex.
It has been inferred that secondary male characters were
potentially present in the hen, but were inhibited by the
ovaries.
Moore implanted a piece of ovary in a young male guinea-
pig. His body was modified ; his teats came to resemble those
of a pregnant female. His behavior showed no sign of
acquired feminine instincts. Another investigator reports
"timid, shy, and mothering-the-young" behavior of a guinea-
pig thus altered. But all investigators agree that the male
gonad transplanted into an altered young female leads to
change in both body and behavior. She becomes aggressive,
quarrelsome, and behaves like a typical male toward other
males and toward females in general. Her physical modifi-
cation is equally profound.
Cattle breeders have long known that the female of
bisexual twins is generally sterile and tends toward the male
in physical characters. Such sterile females are called free-
martins, Lillie investigated. The twins, it seems, develop
independently in the two horns of the cow's uterus, but join
below in the outer fetal envelope. Through this they
exchange blood. The precocious hormone of the fetal male
sterilizes the fetal female ovary! It seems so extraordinary
as to be almost incredible.
But there is no doubt about sterile freemartins, nor about
the fact of their intercommunicating arterial blood stream
in fetal development. Lillie's conclusions mean that the
male fetus secretes a specific gonad hormone before its
gonads are really formed; this male hormone sterilizes the
female gonad.
The fact that both pancreas and thyroid hormones are
225
WHY WE BEHAVE LIKE HUMAN BEINGS
known to be secreted in intrauterine life lends weight to the
inference that the sex hormones themselves are produced by
the primitive germ cells. That there is no exchange of
gonad hormones between the human fetus and its mother
seems evident from the fact that the developing male fetus
does not influence the sex life of the mother.
In other words, while the nature of the sex impulse is the
same in the two sexes, the sex hormones themselves are not
the same. But they are not antagonistic. "Maleness" can
be produced in females; "femaleness" in males. The male
hormone in a young spayed female modifies both her
behavior and her body. The female hormone in a castrated
young male body modifies only the body.
The male fetus does not modify its mother: she is still in
possession of her own gonads. The male fetus modifies the
behavior and sterilizes the gonads of its twin female fetus.
Human twins, if "identical," are always of the same sex;
if not identical there is no exchange of blood, for each has
its own fetal membranes.
10
The adult female gonads in mammals contain ova in
varying stages of ripening and interstitial stroma or cells.
Bodi seem to have an identical origin and both pass through
similar changes in development.
The ova or germ-cells develop in Graafian follicles. When
ripe they burst through the wall of the ovary. The ovum
escapes. The ruptured follicle reassembles and enlarges for
about a week, filling the rent in the ovarian wall. Then it
breaks up and is absorbed before the next follicle matures.
But if the ovum is fertilized, the follicle continues to develop
for three months and then persists until the end of pregnancy.
The ruptured and changing follicle is called the corpus
luteum (yellow body) because of its color after the escape
of the ovum. Corpora lutea are supposed to produce a
226
THE ENDOCRINE GLANDS AND THE CAUSES OF DEATH
hormone. The ovary does produce hormones, how or where
is not well understood; nor, in fact, has the ovary itseK parted
with half of its mysteries.
Removal of the ovary or its absence or atrophy in the
young is followed by an arrest of secondary sexual char-
acters. The primary sexual characters, including the breasts,
remain in an infantile condition. The lunar cycle does not
appear. The body tends toward fat. Removal in the adult
leads to atrophy of the primary sexual characters, the sup-
pression of all sex functions, and of most sex behavior.
The ovary can be transplanted from one part of the body
to another; it long continues to function as an endocrine
gland, no femininity is lost, nor does the lunar cycle cease.
When transplanted from one body to another it may form
blood connections, but it eventually degenerates. But as long
as a piece of it remains alive in its new hostess her sex life,
including lunar cycle, continues "normal."
For transplantation purposes a bit is as good as the entire
ovary. Where, then, does its hormone come from? It pro-
duces one: Carlson thinks probably several. None has yet
been isolated or can be detected in the human blood. But
Allen and Doisy claim to have isolated a mammalian ovary
hormone which resembles the long-desired "love potion" of
romance and literature. "Female animals treated with it
take the initiative in courtship, even at an early age."
Injected into young animals, they "become mature before
they normally would."
This hormone is an "extract of the contents" of the
Graafian follicles. Why not? It is all plausible. Nothing
seems more certain than that the sex impulse and all second-
ary sexual characters in all mammalian females are depend-
ent upon the normal functioning of the ovaries. The
physiological and anatomical changes in the Graafian
follicles during the life cycle are both profound and sig-
nificant. As they are the source of the ova, it is reasonable
227
WHY WE BEHAVE LIKE HUMAN BEINGS
to suppose that they carry the control of sex impulse or
behavior and the acquired secondary characters.
When the follicle erupts and discharges the ovum, it
becomes the corpus luteum. W^en the corpus luteum is
destroyed, pregnancy ends and ovulation is resumed. Hence
the inference that the corpus luteum is responsible for uterine
changes leading to the implantation of the embryo and for
the early growth of the fetus. Wlien corpora lutea are fed
to hens, they lay no eggs; hence the inference that during
pregnancy they inhibit the ripening of the Graafian follicle
and so prevent ovulation and menstruation and restrain the
sex impulse. They influence the mammary glands, but the
development of these during pregnancy is believed to be due
to hormones from the fetus to the maternal blood. The
mammae themselves are not known to have any endocrine
function. Their removal does not prevent child-bearing or
have any other effect than "psychic and cosmetic," according
to Carlson. But removal of the ovary is removal of feminine
nature.
No mammals below Primates have anything approaching
the specific lunar cycle of a woman's life between puberty
and the menopause. While slight menstrual hemorrhage
occurs in many species of Primates, it is essentially a human
process regulated by the normal and mature ovum, but its
function is not yet understood nor is there agreement as to
just what takes place or why there is such wide range of
individual variation. The climacteric is reached when no
more Graafian follicles mature.
Disordered sex life — except the menopause — in woman
may be due to other than ovarian deficiencies: other endo-
crines may be involved, perhaps the adrenals or the pituitary.
It is not certain that ovarian extracts are anything but
extracts and so of possible value only through suggestion.
Nor can luteal extracts check human ovulation; the corpus
luteum can. Nor is it at all certain that any ovarian extracts
on the market contain any hormone. It is certain that the
228
THE ENDOCRINE GLANDS AND THE CAUSES OF DEATH
normal ovary, through its hormones, functions for all second-
ary female characters and has the specific sex functions for
such distant organs as uterus, placenta, and mammae.
The functions of personal incubation assumed by one-half
of the race ages ago necessitated an elaborate internal
mechanism. For its perfect functioning, elaborate and com-
plicated controls were necessary. It follows, and is
biologically inevitable, that the sex life of the female of the
human species is far more complex than is that of the male.
But it is biologically conceivable that in a no great distant
future reproduction in the human species can be radically
altered. Under such controlled breeding, the ovaries of only
physically sound individuals would be used and to the limit
of their two hundred ova; these would be fertilized artificially
and developed in man-made incubators. Such control of
human life seems quite attainable; much more so than the
synthesis of life in any form.
11
The male gonads contain spermatogonia. These develop
into germ-cells and fertilize the ovum. This involves two
factors: the ovum is stimulated to develop; the male inherit-
ance is afforded a vehicle. The gonad performs this
function through external secretions. But as the spermato-
gonia themselves are cells early set aside in embryonic
development and are not products of chemical change as are
the secretions of other duct glands, the gonads in their repro-
ductive functions are not comparable to other glands. They,
as the ovaries, are arsenals where ammunition for life is
cultivated.
Between the cell clusters where spermatogonia develop are
other groups of cells, the interstitial cells of Ley dig. These
cells appear in the embryo before the spermatogonia cells.
Under the X-rays they are not affected; the sperm-cells are.
When the gonad does not descend, or in one transplanted into
229
WHY WE BEHAVE LIKE HUMAN BEINGS
another body, the germ-cells atrophy; the Leydig cells are
unaffected or may increase in size. Thus they show greater
power of resistance than the germ-cells; they are embry-
ologically older.
Absence, atrophy, or extirpation of the gonads in the
young male prevents the appearance of the secondary sexual
characters — beard, change in the larynx and character of
skeleton — and checks development of the reproductive
mechanism. It also delays the final ossification of the heads
of the long bones and the sutures of the skull. It lowers the
rate of metabolism, increases the tendency to take on fat, and
lowers vasomotor irritability. It perhaps leads to changes in
the endocrine system, enlarging the adrenal cortex and the
pituitary, diminishing thyroid growth, checking thymus
involution. It changes behavior: less bold, less pugnacious,
more infantile; it shuts off the sex impulse. In the adult,
loss of gonads stops the sex impulse and tends to atrophy
of the reproductive mechanism, to obesity and lowered
metabolism.
Nothing else. Life is not shortened, nor mental or
physical efficiency impaired. Hence, as Carlson points out,
"growing old" is not to be charged to gonad dysfunction, but
to damage by age to all the tissues of the body. Gonad
removal leads only to loss of structure and function specific
for sex life.
Curiously, evidence seems to indicate that gonadectomy
in the two sexes leads to opposite changes in the adrenals:
in males, to an increase of 15 per cent; in females, to a
decrease of 20 per cent. The net result is to increase the
resemblance between the two sexes.
The spermatogonia cells are simply future germs. This
throws the responsibility for the regulation of the develop-
ment of sex mechanism and function on the interstitial cells.
Moore has recently furnished new proof of this. In
cry ptor chic individuals (the gonads remain within the
abdominal cavity) there may or there may not be spermato-
230
THE ENDOCRINE GLANDS AND THE CAUSES OF DEATH
gonia; if not, the individual is, of course, sterile, but if the
Leydig cells are present, the individual is male in structure,
function, and behavior.
When the vas deferens or excretory duct of the gonad is
ligatured, the spermatogonia are said, but not proved, to
atrophy; the germ-cells cannot, of course, be discharged and
consequently the individual is sterile. But as long as the
Leydig cells are intact, sex life is unimpaired. This is the
basis of the famous operation of Steinach, and is based on
two assumptions: that ligation of the vas deferens increases
Leydig cell growth; that it causes the spermatogonia appa-
ratus to atrophy. Neither of these assumptions is yet proved;
in fact, Oslund asserts that both assumptions are contrary
to fact, that vasectomy produces no testicular changes and
"cannot be looked upon as a method of causing rejuve-
nescence."
When gonads are transplanted into other male bodies, the
individual maintains sex life as long as enough Leydig cells
remain alive. This was Steinach's first method of "rejuvena-
tion": "a biological futility, a catering by the surgeon to the
elements of sex degeneracy," says Carlson. And adds : if the
transplant be from goat or monkey, "the surgeon is the
monkey, the patient is the goat."
Grafts of goats or monkeys are not yet known to become
vascularized, nor is it known that the Leydig cells survive
up to two years. It is known that the sperm-cells do not
survive transplanting. It is not settled how long a gonad will
live after removal: "most glands die in a few hours." At
most, the graft can only temporarily restore the sex impulse;
any true "rejuvenescence" of mind or body can only come
from suggestion.
Suggestion likewise, thinks Carlson, is all that backs the
whole tribe of "genital" extracts on the market and which
are guaranteed "cures" for everything from growing pains
to melancholia, including goiter, scurvy, cholera, anemia,
delirium tremens, and syphilis.
231
WHY WE BEHAVE LIKE HUMAN BEINGS
The adrenal cortex and Leydig cells have a common
embryonic origin, but they come to have quite different
functions. No gland can play the role of the Leydig cells;
if they are lost, sex life is lost. The only compensation
possible is in the direction of general metabolism.
In both sexes, gonad hormones are specific regulators of
sex characters up to puberty; the hormones that sustain sex
life during maturity are possibly quite different from those
which determined development. They are the catalyzers of
development; they must vary with the stage or degree of
development.
12
The race of bisexual animals depends on the coming
together of male and female. Moths find their mates by
their olfactory antennae; fishes, by color and behavior; frogs,
by voice and touch; birds, by voice and sight; mammals, by
scent. Man is a mammal, but he has traded his scent organ
for a nose and he kills his odor with soaps or artificial
scents. He discovers his mate, as do birds, by voice and
sight. Either sex, deprived of the gonads, has no need for
secondary characters; nor do they appear unless the gonads
function as endocrine or "puberty" glands. That is the busi-
ness of the hormones of the gonads : so to catalyze developing
structure that the two sexes already determined in prenatal
development will not look or sound alike, but will look and
sound good to each other. Secondary sex characters, there-
fore, are additional devices of nature for making each sex
easily recognized by and more attractive to the opposite sex.
Hence the "instinctive" repugnance of normal men for
"manly" women; of normal women for "womanly" men.
Puberty means sexual maturity; the individual is ready
to assume the next stage in normal development: parentage.
Modern life departs from the normal; it pays no attention to
the facts of puberty. The age of marriage tends to become
232
THE EXDOCRLXE GLANDS AND THE CAUSES OE DEATH
more and more remote from sex maturity; the education of
the youth proceeds as though tliere were no such tiling as
puberty.
In normal life in girls, as in the females of all mammals,
the milk glands at puberty take on rapid growth. The most
noticeable changes in the boy are the appearance of hair
on the face and a startling change in the growth of the
cartilages and vocal cords of the larynx. The voice at first
breaks; by die time it becomes normal again it has, as a rule,
dropped one full octave. Mean^vhile the boy outgrows his
collars faster than he does his hats. In bodi sexes hair
appears on the pubes.
^Tiile early growth depends on the amount and nature of
the food and on general hygienic conditions, puberty as a
rule appears earliest in individuals of short stature. Thus,
it comes earlier among Italians than Scandinavians, the
difference agreeing widi die relative statures of the two
peoples.
Girls of European descent grovr faster than boys between
the ages of ten and fifteen. Between eleven and fourteen the
girls are actually taller; between t^v^elve and fifteen, heavier.
At fifteen the rate of the girTs grov.th begins to diminish.
The skeleton begins to mature, for both sexes, at puberty-.
The girl's pelvic girdle undergoes a marked change in width.
She also becomes more plump.
Between the fourteenth and eighteenth years for girls, and
bet^veen die fifteenth and t^ventieth years for boys, a new
im.pulse enters life. This impulse, only vaguely present
before, is now the impelling force. For this reason: puberty
means more than mere physical change, it means sex
maturity; it is a result as well as an event. Besides the
physical changes which increase the demands for food-
energy*, the whole organism is involved in maturity.
The boy or girl is now preoccupied with a new order of
internal affairs. This necessarily involves the entire nervous
mechanism — not in its structure, but in the nature of the
233
WHY WE BEHAVE LIKE HUMAN BEINGS
situations to which it must now adjust the individual. The
second great crisis in life is at hand. It is a different indi-
vidual, the world itself is different. Up till now the
primordial instinct of self-preservation has had only one
main drive: food-hunger; to this is now added the drive of
mate-hunger. It enters the race fresh and will have its say.
The body itself, under both direct and indirect influence of
the sex mechanism, is stirred to its depths. The inhibitory
centers in the spinal cord are lowered; the susceptibility of
the brain is increased through the vasomotor nerves.
The outcome of the conflict is determined by many
factors. In animal life and the majority of the human race,
the result is courtship and mating. We generally solve the
problem satisfactorily, but promiscuity and certain unbi-
ologic and unsocial habits, with sex complexes leading to
neuroses, seem to be increasing.
But the real point in all this is that the gonads normally
do function as endocrine glands. As a consequence the
two sexes do differ, in bodily structure, in behavior, in
organic necessity. As Ellis puts it: "A man is a man to
his very thumbs, and a woman is a woman down to her little
toes." Specialization in bodies is older than civilization,
and there has always been a real difference between men
and women beyond that of the primary sex organs. Which
prompts Keith to remark: "No legislation can blot out|
structural differences that have taken geological epochs to I
produce." But substitution of gonads can. In fact. Riddle
cites two cases of female birds that laid eggs and were in all
respects true females; they ceased to be females, became
males in form and function, and fathered young. No sur-
gical operation involved: only destruction of female organs
due to tuberculosis; male organs replaced them, followed by
male behavior. What all this signifies is not yet known.
But this much, at least: sexual characters depend on sex
hormones; complete sex-transformation in adults is possible.
234
THE ENDOCRINE GLANDS AND THE CAUSES OF DEATH
13
Shorn of her locks and dressed in man's costume, woman
is still woman. Yet how many times she has passed for a
man — as a sailor, a soldier, a coal-miner! Her femininity
tends to disappear beneath the male's make-up. The two
sexes differ in degree rather than in kind.
The assumption that women are not as "adult" as men
has no basis in fact. Yet we keep hearing about the
"infantile" character of woman! Her body does more nearly
resemble the infant's than does the male's, but this only
states half the truth. In all that is essentially "human," her
body is more human than man's. The adult male may be
less infantile than the adult female ; he is also less essentially
"human."
The typical female skull is so delicate and smooth that
sex can be postulated nineteen times out of twenty. It has
none of the asperities, ridges, and prominences which mark
the skull of the male. The bones of her face, especially of
the jaws, are much more "human" than are the corresponding
bones in man's jaws.
The weight of the skull compared with the weight of the
long bones shows this interesting progression: greatest pro-
portionate weight of skull, children first, women next; then
short men, tall men, apes. In weight of skull compared with
that of thigh bones, the advantage again is with woman.
Our pelvic girdle is in some respects more "human" than
the skull itself. It is the distinguishing sex trait in the skele-
ton. To the trained observer there is no mistaking the pelvic
girdle of a female for that of a male. A moment's reflection
will show why this should be so. In man, the pelvis supports
the abdominal viscera and continues the support of the
upright body from the legs. To perform these two functions
it became modified in two directions: broader, by expansion
of the iliac crests; more compact and substantial, by a
greater, broader sacrum. The sacrum is the key of the
235
WHY WE BEHAVE LIKE HUMAN BEINGS
pelvic arch; it carries the backbone, and incidentally the
entire upper part of the body. Woman's pelvis has traveled
further than man's in this regard. Her breadth across iliac
crests is proportionately greater than the depth from pubic
symphysis to top of sacrum. Her sacrum also is more dis-
tinctively human in its great breadth.
The two bones which form the basin of the pelvis — of
which the iliac crests are easily felt beneath the skin at the
sides of our abdomen — meet in front to form the pubic
symphysis. The joint of the symphysis is made by a strong
ligament which yields under pressure. In the male pelvis the
ligament is narrow; in the female, wide. The slope of the
pubic bones below the joint is also greater in the female, an
additional factor in enlarging the outlet of her pelvis.
Can our pelvic girdle become more "human"? The upper
rim might become better adjusted to support the body, but
a girdle so narrowed as to prevent childbirth stops variation
in that direction. This seems to set a limit to the size of the
human brain at birth. In most still-born deliveries the head
is too large to pass the bony outlet of the pelvis. We may
assume that the limit of brain size at birth has been reached.
Man's pelvis is long, narrow, strong; woman's, broad,
shallow, delicate, roomy. Her thighs are relatively greater.
Her carriage differs from man's because the heads of her
thigh bones are farther apart. As she transfers her body
from one thigh to the other in walking, she must make a
greater effort. Her pelvis is a compromise between an arch
to support viscera and an outlet to make childbirth possible.
Women among so-called savages are notoriously as strong
as men, although there is always a division of labor between
the sexes. The most splendid human bodies I have ever
seen were those of black women working under extremely
primitive conditions in gold and emerald mines in South
America. Their backs, shoulders, and arms spoke of great
strength, but there were no bulging muscles. Even apart
236
THE ENDOCRINE GLANDS AND THE CAUSES OF DEATH
from their breasts, their bodies were unmistakably
"feminine."
The luxuriant head hair of women of European descent is
not a mark of sex: it is the barber that makes — or made —
the difference. Chinese and Indians were proud of their hair
and had as much of it as their spouses. Head hair is a race
and culture and not a sex factor.
Sex differences are strongly marked in brain size among
man and apes. The male gorilla's brain is 18 per cent
larger than the female's; the orang's, 14 per cent; the chim-
panzee's, 8 per cent; man's, 12 per cent. But the disparity
is due to general disproportion in size between the two sexes.
Structurally the brains of the two sexes are the same, and as
compared to weight of body are heavier in women than in
men. If a relatively large brain is a "human" trait, the
brain of the child stands highest, woman next.
More males are born than females; in the so-called white
races, about 105 males for every 100 females. Yet woman's
longevity counter-balances the disproportion; at the age of
fifty, unless migrations or wars upset the calculation, we may
expect to find as many women as men.
Differences between the tv/o sexes, yes. The male spe-
cializes in the direction of brute strength and the courage
that goes with it; the female retains her youthfulness in body
in general and especially in face and neck. With age some
women begin to appear neutral, halfway between man and
woman. But the vicious element in such phrases as
"Woman's proper work" and "Woman's true sphere" is the
assumption implied of lack of capacity. To assume that her
capacity for intelligent behavior or human adjustments is
less than man's is biologically and physiologically absurd.
Comte's idea is better biology and sound psychology:
"Between two beings so complex and so diverse as man and
woman, the whole of life is not too long for them to know
one another well and to learn to love one another worthily."
237
WHY WE BEHAVE LIKE HUMAN BEINGS
14
The endocrines are new to science ; some have only recently
been discovered; the function of some only recently sus-
pected; not one is yet perfectly understood. Yet their
astounding importance, and the claims quacks make that
gland "extracts" are cure-alls and gonad operations a Foun-
tain of Youth, conspire to whet the appetite for facts faster
than the laboratories can sift them out. Hence new crops
of quacks who dispense pills or elixirs or their services with
a knife or a ligature; and a raft of literature which, as
Hoskins says, "for its vagaries, fantastic exuberance, and
wholesale marvel-mongering, is without a peer in the history
of modern science."
Little is yet known of endocrine co-operation, or what takes
place in some when others fail. No gland or other organ
functions for or by itself, or lives a life of independence;
the entire body mechanism makes up the organism. The
business of the glands is the business of the body as a going
concern, to keep it fit and enable it to function, as infant,
as youth, as adult, as senility overtakes it.
Carlson thinks the following endocrine teamwork proba-
ble: the gonads cannot function if the thyroid and possibly
the pituitary and adrenal cortex are subnormal; removal of
thyroid and probably of gonads stimulates the pituitary;
thyroid extract seems to stimulate the adrenals and the
pituitary, as it does the heart, liver, and kidneys; removal
of the thyroid stimulates the parathyroids — at least in tad-
poles; tumor of the adrenals induces gonad precocity;
removal of the gonads retards atrophy of the thymus and
leads to change in pituitary and adrenal cortex.
It seems certain that removal of the thyroid is followed by
cretinism in children, myxedema in adults; of the para-
thyroids, by death; of the pancreas, by death; of the adrenals,
by death; of the pituitary, by infantilism in children, by
impotence in adults; of the thymus, by sexual precocity; of
238
THE ENDOCRINE GLANDS AND THE CAUSES OF DEATH
the gonads, by sex infantilism in children, by atrophy of
secondary sex characters in adults; of the pineal, by no
known endocrine effect.
Most of each endocrine may be removed from an animal
without apparent loss of function of its internal secretion;
the inference is that no endocrine normally works to its full
capacity. A normal thyroid stores up enough to last several
weeks ; the adrenin reserve only suffices for a few hours. But
in general almost nothing is known of the storage capacity
or rate of production of hormones. It is known that symp-
toms may not appear after removal of the thyroid for weeks
or months. Removal of the pancreas is followed by
symptoms within ten hours ; of the parathyroids and adrenal
cortex, almost at once.
Post-mortems prove these connections: thyroid with
cretinism and myxedema; adrenals with Addison's disease
and death; pituitary with infantilism; pancreas with diabetes.
Known positive results from large endocrines or excessive
endocrine secretions are few; it is not yet proved that large
glands yield large results. It is only inference that excessive
thyroid secretion causes toxic goiter; of the anterior lobe of
the pituitary, gigantism; of the adrenal medulla and the
thyroids, excess pep; of the adrenal cortex, the pineal and
pituitary, sex precocity; of the gonads, excessive sex urge;
of the thyroid, diabetes. Results claimed for excessive
thymus and pineal activity are not yet proved. As their loss
produces no known effect, what could necessarily result from
their increased function?
Can endocrine disorders be "cured" through the nerves
of endocrine secretion? The pineal, the posterior lobe of the
pituitary, and the medulla of the adrenals are themselves
modified nerve cells. But, except the medulla, neither the
cutting of all the nerves to all the endocrines nor artificial
stimulation shows any effect on the body or change in the
glands themselves. The nerves to the endocrines seemingly
have little or nothing to do with their secretions. But most
239
WHY WE BEHAVE LIKE HUMAN BEINGS
quacks feed their patients "gland extracts." Few hormones
are yet known. Apart from insulin, adrenalin, pituitrin, and
thyroxin, the quacks themselves know nothing further of any
of the various extracts they often feed for unknown diseases.
With "diet and rest," extracts are as potent as the bread pills
of old.
The endocrines are part of the body, and so subject to
heredity, tumors, lesions, tuberculosis and other infections,
especially to faulty metabolism. The influence of the thyroid
and pancreas on general metabolism and growth is funda-
mental. They must, therefore, influence all the body, includ-
ing all the glands. The thyroid normally functions only if
there is enough iodine in the food. If in doubt, take cod-
liver oil or eat sea grass.
75
The endocrine glands are intrinsic parts of the body, in
intimate touch with living processes. Muscular activity
starts the sweat glands, the muscles are fed with sugar, the
adrenals pour their secretion into the blood to neutralize the
toxins of fatigue, and so on.
Arrest of development or over-stimulation of the endo-
crines brings about change which may be harmful or of
benefit to the body. Giants, fat women, cretins, men and
women under-sexed and over-sexed, imply variation in tlie
structure and functioning of these glands. Apparently some
individuals are better fitted for the work of life than others;
still others are so well fitted that they overdo it. No two
human beings are exactly alike; they do not and cannot act
alike. We should hesitate before passing harsh moral judg-
ments upon activities due to inherited or acquired physical
structure.
Possibly several generations must pass before the real and
definite function of the endocrines is fully understood. Possi-
bly new drugs will replace the old; pills compounded on
240
THE ENDOCRINE GLANDS AND THE CAUSES OF DEATH
formulae learned in nature's laboratory, elixirs for all the
ills of body and mind we are now heir to. The fact that
the emotions are expressions of states under control of the
glands and closely bound up with the sympathetic nervous
system opens up an enormous field for speculative possi-
bilities. Russell thinks it will be possible to make people
hot-headed or timid, strongly or weakly sexed, and so on,
as may be desired. In case of war the timid souls will simply
be injected with certain glandular extracts or synthesized
regulators !
There is another angle. Almost nothing has yet been done
on the racial anatomy of the endocrines. Are shape and
size of head, face, nose, eyes, teeth, lips, length of limbs,
and stature, character and shape of hair, due to the activity
of the endocrines? Keith thinks this possible and suggests
that whites are what they are because they have more thyroid,
adrenal, pituitary, and gonad hormones than other races, and
that inherited condition of glands points a mechanism through
which heredity controls development and established type
variations. Racial character — such as emotional reactions,
intellectual capacity, and personality in general — would thus
vary likewise, and for the same reason.
This compounding of elixirs for all ills from endocrines,
and the solution of the problem of race and individual varia-
bility by reference to variation in glandular mechanism and
functioning, take us too far from reality, too far into possi-
bilities. We of to-day are going concerns and our interest
in the past is only in the light it can shed on what we are
and can do to-day. And that is a personal question — for
this reason:
No two human beings are alike. Every human being con-
tinues throughout life to change. The question. What is
good for the human machine as a going concern? is, there-
fore, always personal and individual; it all depends. Some
want to go fast, others prefer to go slow. One may see ideal
life only in the chest of Hercules; another, in the wings on
241
WHY WE BEHAVE LIKE HUMAN BEINGS
the feet of Mercury. But most humans are born right; there
is nothing the matter with our inheritance.
There is a normal rate of growth and of growing old.
Too much or too little upsets the normal rate. With nothing
to chew on, normal development of jaws, teeth, muscles and
glands of mastication need not be expected. Without work
or play, normal development of the bones and muscles of
the motor mechanism is not to be expected. "Exercises" and
"physical culture" are too often taken as pills and drugs:
controls, but not cures.
Glued to a chair with head tied to an account book or a
last makes for less than the normal work designed by nature
for heart and lungs. By and by lungs and heart lose their
original capacity for work, as do muscles which are never
extended.
Man has inherited a body of a certain type which functions
best under certain conditions of food, work, rest, sleep, etc.
These conditions also are part of each individual's inherit-
ance and consequently must vary with individuals. Sauce
for the goose is not necessarily sauce for the gander. It is
true that some Jack Sprats can eat no fat, their wives can
eat no lean.
The real question, then, for adults, is personal. Is my
machine capable of giving the service I shall require to
carry me where I want to go? Many are ready enough to
answer. No. But they are not willing to distinguish between
hunger and appetite or count calories instead of cost; and
they will walk a mile for a cigarette, but not a foot for
health's sake.
But every child is entitled, in civilization as in savagery,
to the full development of its normal inheritance. Civiliza-
tion has taken curious, often monstrous, bents; and even
now in many places does not hesitate to deny children the
free exercise of their human birthright to develop sound
minds in sound bodies.
242
THE ENDOCRINE GLANDS AND THE CAUSES OF DEATH
16
"How can a man be born when he is old?" asked Nico-
demus. And answered his question with another, "Can he
enter a second time into his mother's womb and be born?"
Life does grow old and young again, but nature knows of
no such rebirth as puzzled the brain of Nicodemus and has
become entangled in the folk-customs of so many peoples.
Growing old and growing young again are age changes, both,
in Child's words, "merely one aspect of Werden und
Vergehen, the Becoming and Passing-away which make up
the history of the universe."
What is it that grows old and young again? "Life" grows
old. What is "life"? We have certain criteria — none too
good — for living beings; and certain criteria for death. But
life itself, can it be defined or described? Is it a thing or
an action, a process or a function? There are living beings
and processes or functions of living. But life cannot be
restricted by this or that process or function, nor described
as this or that chemical compound; nor as any one certain
or particular form. Life is something more than process or
function, compound or form.
Life is a result of action in something. The "something"
is a physical body of protoplasm. The "action" is change,
many and complex and dynamic. Dynamic changes and
physical body are inseparable; they influence and condition
each other.
Man himself is such a physico-chemical system of dynamic
changes. What disturbs this system disturbs the being; the
being is the system. If the disturbance is so great that the
being cannot readjust itself, the system breaks down, the
being dies.
Probably we shall never know just how life itself began.
If we could concoct a reaction-complex capable of living,
we might not know just when life begins. The complex
243
WHY WE BEHAVE LIKE HUMAN BEINGS
structure and the dynamic process known in living beings
are always bound by a bond which, broken, ends life.
Hence life is unlike any machine made by man. In
machines, dynamic processes take place in complex struc-
tures, but we can always distinguish between process and
structure. Nor can the machine function until the structure
is completed. But the living being always functions and
has been functioning since life began. The structure deter-
mined function, function determined structure. In other
words, life constructs its own machine by living.
Living means changing. Living processes depend on
change. The body during growth adds to itself certain chem-
ical compounds which are physiologically stable; that is,
they are of such a nature that they can be built into the body.
The energy used up during the building or growth period
is furnished by the oxidation of less stable compounds.
The growing child is a rapidly changing being. We age
fastest during childhood. The rate of metabolism is then
highest. In old age it slows down. In starvation, new com-
pounds are not synthesized as fast as old compounds are
broken down. But starvation only ends in death after many
weeks because the most vital functions are carried on in the
most active organs. Because of their activity they are fed,
first by stored fuel or fats, next by muscle. When this fuel
is exhausted, death soon follows.
Thus, growing and growing-old are simply two aspects of
the same complex dynamic activity. Both are phases of
production and progress. We shall know how to grow young
when we know how to increase the rate of metabolism or
vital change, and how to change the cells of the body so that
an increase in rate of metabolism is possible.
The nature of the rejuvenescence that hinges on the internal
secretions of the sex glands is not part of the problem raised
by Nicodemus. A man "renewing his youth" is one thing;
Life growing young again is quite a different thing.
Life resides only in living beings; the way they are born
244
THE ENDOCRINE GLANDS AND THE CAUSES OF DEATH
again when old is one phase of evolution. The process is
called reproduction, of which there are many methods. Have
they all something in common? Or is there some unique
quality in reproduction in man and higher animals not found
in the lowest animals? Whether there is or not, the fate of
the individual organisms concerned is different. Those that
reproduce by division do not die; at any rate, as Weismann
said, there is no "corpse." Death does overtake those that
reproduce bisexually. But reproduction in man is bisexual.
Man, as individual, dies; he cannot be born again when he
is old, or young. The life that is in him can grow young
again; but only by a process known as reproduction. That
is the nature of reproduction.
Rebirth, then, as that word is commonly understood, is
biologically inconceivable. It is possible that to-day complex
chemical substances are in process of becoming of the nature
of protoplasm in which living reactions take place, and which,
could we observe them, would be recognized as living beings.
But the laws of chance are against it and all our conceptions
of evolution are against it. A possible "rebirth" is quite as
improbable.
All that is known of the facts of evolution and all theories
as to the mechanism of evolution favor the idea that every
man and every being alive to-day have been alive since life
was evolved. It is even more certain that every man and
every organism alive to-day began life as part of an adult or
"old" organism. But as man and all organisms begin their
individual existence as young organisms, it follows that
something, somewhere, somehow, has renewed its youth, has
become young again.
Call this "something" life. Life itself has grown old
during evolution. The life that is in man and in all living
beings is old, millions of years old; it grows young through
reproduction.
There are only two great kinds of reproduction: without
sex or agamic (no wife), and with sex or gametic (wife).
245
WHY WE BEHAVE LIKE HUMAN BEINGS
In agamic reproduction, a new individual arises from part
or parts of the body which have come to lie beyond tlie
physiologic limit of size; they are physiologically isolated
parts of the body. In gametic reproduction, as in man, the
germs of life are also isolated — so far as the parent indi-
vidual is concerned, "dead and shed," Child says. But by
adult life they are also already highly specialized and have
already completed their growth.
Weismann assumed that the germ-cells are young and that
they are special only in the sense that they are set aside at
once in embryonic development for the purpose of reproduc-
tion; hence the doctrine of the "continuity of the germ-
plasm." He also assumed that nothing could influence these
cells; hence there could be no transmission of a character
acquired by the body of the individual carrying these cells.
But germ-cells in bisexual reproduction are in no sense
"young"; they are no more "special" than any other group
of cells of the body. Only after the embryo has begun to
build its body are the cells resulting from cell divisions set
aside to become the store of future germ-cells.
Ovum and sperm are old cells, especially the sperm. They
are as differentiated as almost any cells of the body. They
have ceased to grow; they have a low rate of metabolism;
but the dynamic substratum present in both is old protoplasm,
grown old during the long years of evolution. As a result
it has become stable, highly individualized. Otherwise there
could have been no evolution of such structural permanence
and complexity as we find in man and higher animals.
Hence evolution is not chiefly change in form, but change
in the dynamic reaction system of protoplasm. As indi-
vidual man develops and grows old, so evolution itself repre-
sents a change from a less stable to a more stable condition
in the dynamic reaction system.
The protoplasm of the germ has also evolved. As a result
of that evolution, it has reached such a stage of diff'erentiation
that it can no longer react alone, as it does in lower organ-
246
THE ENDOCRINE GLANDS AND THE CAUSES OF DEATH
isms. Only by marriage of ovum and sperm is the carrier
of life brought back to pre-embryonic conditions. Fertiliza-
tion is the only rejuvenescence known to man and higher
animals.
By fertilization the old protoplasm of the ovum is recon-
stituted, reduced, rejuvenated. The fertilized ovum is
younger than ovum and sperm were before they united in
fertilization. It begins life anew; and as a parasite. Having
escaped from the old individual, it is no longer subject to
the inhibitions of the old. Not until it begins its post-natal
existence will it be subject to the inhibitions of human society.
The fertilized human ovum is possibly less an "individual"
than a protozoon, but that ovum is protoplasm which has
been evolved to the point that within it is potentially present
the foundation of the structure and form of an adult man or
woman. That ovum can do what the growing child does: so
transform food materials that it can build some into new
protoplasm and incorporate the new within its body; it can
oxidize other food materials to set free the energy it uses in
building its body. This transformation of food materials is
metabolism, change, the foundation of the function of life.
Life itself, then, is change in protoplasm, itself a dynamic
entity. Change or reaction is determined by its physico-
chemical constitution and by its relation to the external world.
Adaptations are thus seen as simply special features of this
relation. The mechanism by which life renews its youth is
such an adaptation.
I agree with Child that it is impossible to conceive of evolu-
tion and of so-called "adaptations" without assuming that
"acquired characters" can be inherited. But often, as Child
points out, tens of thousands of generations may have been
necessary for such inheritance to become appreciable.
Without such adaptation there would be no such living
beings as man and higher animals. There might be some-
thing else "just as good," for, as Russell says, we have only
our own word for it that man is superior to the ameba; we
247
WHY WE BEHAVE LIKE HUMAN BEINGS
can have no idea what the ameba would think of the
proposition.
Nor need it necessarily disturb our self-esteem to realize
that only our own conditioned human eyes see man as a
"finished product" of evolution. Pearl aptly argues that
Omnipotence could have made a much better machine than
the human body — "that is, if he had first learned the trick
of making a self -regulating and self -reproducing machine.
Each part of the human body is only just good enough to
get by — workmanship like that of an average man. If evolu-
tion happens to be furnished with fine materials it has no
objection to using them, but is equally ready to use shoddy
if it will hold together long enough to get the machine by
the reproductive period." Which is another way of saying
that evolution's main concern is the continuation of life rather
than of this or that kind of living beings.
But this does not necessarily mean that senility and death
are the inevitable ends of human existence, either as indi-
viduals or as race.
17
Man and other warm-blooded animals are killed by
freezing or by boiling, or by cutting off their air or food
supply. Death comes also in other ways: foreign substances
are taken in, or get into the body, which cannot be eliminated
or combated; or vital parts of the body are injured by
mechanical or other means. In other words, we die when
the conditions necessary for life have been so changed that
life becomes impossible.
We are specific mechanisms in which certain physico-
chemical changes occur in a certain routine order. We live
as long as the mechanism is in good repair and the changes
take place. Mechanism and changes are one. They only
seem two when life is looked at from diff'erent angles.
Together, they represent life: they balance; they are in
248
THE ENDOCRIiNE GLANDS AND THE CAUSES OF DEATH
equilibrium; they are adjusted; they harmonize. Normally
they go through life together, always preserving this har-
mony. Cut off a leg: the blood does not stop circulating;
it readjusts itself to the changed condition. If it cannot
readjust, what is left of the machine stops.
Anything which necessitates serious readjustment is
pathologic. The body is diseased when under conditions to
which it is not adjusted. There are almost as many diseases
as there are cells in the body; certainly many more than there
are tissues or organs. Disease in any cell, cell-group, tissue,
organ, or system, is felt everywhere. The noise of a tooth-
ache may be faint by the time it reaches the toe, but the toe
is none the less interested. A gallstone may be of particular
concern only to the liver, but the liver's concern is the body's
concern.
Life is played to a certain tune; it need not be a monkey-
wrench to set its chords jangling. An undigested bean will
do, or a bean in the windpipe; or any one of a thousand
things. But despite the nicety of the balances and co-ordina-
tions which make for normal health, the body's capacity for
readjustment is remarkable. It is not we who fight for life,
but our living bodies. They hang on to life in spite of much
we do to discourage them.
This fighting power is part of our inheritance. We cannot
grow a new limb, much less a new head or a new trunk, as
some animals can. We can store fuel fat as no lower animal
can; and experience, as no other animal can. It is not to
be charged to our inheritance if we fill our experience-loft
with rubbish. We can make repairs; in some tissues, very
extensive repairs. We can make antibodies.
These antibodies illustrate the vast numbers and the
enormous complexity of the processes that go on under our
skin, and the fine adjustments that must always be going on
to keep the body tuned up for the business of life.
Something seems to happen when the body faces civiliza-
tion. There is probably not a single adult in this country
249
WHY WE BEHAVE LIKE HUMAN BEINGS
with a body in perfect tune: what the life-insurance com-
panies would call "Glass AA risk."
Of 1,000 employees examined by one motor company,
just 1,000 were imperfect. Of a group of hundreds of
thousands examined, 10 per cent had "slight defects," the
other 90 per cent had "defects not so slight." Nearly 40
per cent of the white school children of Washington have
defects — ^teeth, vision, hearing, etc. — ^which can be located
without removing their clothes. Over 45 per cent of Penn-
sylvania's youth were not physically fit to be sent overseas
to be shot at.
This means two things.
More get past Cultural Selection than Natural Selection;
the openings in the sieve are larger, the nature of the struggle
is different. Runts which grow to Roosevelts and Steinmetzes
in civilization die early in nature. Runts which become
nothing but charges on society also survive in Cultural
Selection. In other words, individuals with inherited or post-
natal defects live because society supplies that which their
bodies lack to maintain a balance on life. A freak in nature
does not live long; in civilization, it makes good money.
Millions of minor defects are due to bad food-digestion.
We inherit omnivorous teeth and thirty feet of alimentary
canal made for every kind of food but cooked and pre-
digested. Also, powerful muscles hung to strong bones,
leveraged for work. The body was built on the theory that
these muscles would be worked. The very work the muscles
are supposed to do is part of the process of living. The
flow of lymph and the circulation of the blood in general
depend on a mechanism built to function best when the motor
apparatus is in motion. That is why we have bones and
muscles, and that is why we have blood and lymph.
One bad tooth in an ancient skull or among savages is an
anomaly. A perfect set in an adult American is a far greater
anomaly. Toothache means that the cavity is almost in to
the nerve. That means almost in to the entire body. Our
250
THE ENDOCRINE GLANDS AND THE CAUSES OF DEATH
body is a double sack, each sealed up tight. Whatever breaks
through the wall of either sack (skin or alimentary canal)
is a foreign body and potential death.
Apart from congenital influence, most defects originate in
the mouth or alimentary canal. Children are not born with
defective gums, bad tooth germs, narrow palate, stunted jaws,
adenoid growths, or diseased tonsils. Our inheritance is
usually all right; we do not use it according to directions.
The newborn comes with a full set of tools for building a
full-grown, sound, healthy, defectless body; too often it is
treated as a cunning little toy to a doting household for six
years or so, and is thereafter chiefly of interest to the
statistician collecting Defects or Defectives.
Metabolism is adjustment for the functions of life. We
inherit an adjustment machinery adapted for a certain kind
of active life, but before it is of age we have taught it a
"civilization" that was never contemplated by the designer
of the machine. Civilization is kept busy keeping the
machine in repair.
One good defect deserves another. Defects lead to other
defects. Many bodies are kept so busy repairing leaks in
the lungs, or picking cinders out of the fuel, or keeping
foreigners out of the blood, that they have no time for the
main business of life: giving their owner a lifelong joy-ride.
18
Weismann held that death is an "advantageous adapta-
tion." For what? To whom? Looks like nonsense. Osier
said that man is as old as his arteries. There was enough
truth in this to make it take. It means even less to say that
man is as old as his endocrine glands. Arteries and glands
are as old as the man.
Metchnikofl' held that because of "disharmonies" in the
body, the phagocytes devoted too much time to eating pigment
in hair and too little to the bacterial flora of our digestive
251
WHY WE BEHAVE LIKE HUMAN BEINGS
tract. Result: fermentation, poison, death. His theory beat
the gland-treatment theory into the drug stores, but sour milk
is losing ground as a cure for old age.
Puberty is a period, but a kind of sex life begins at birth;
for many, real sexual maturity never comes. So it is with
adults; some are more adult in body and mind at fifteen than
others at thirty-five; some hurry through to senility before
body and mind have become fully adult. Normal old age
is physiological; it is no more a disease than adolescence,
and should be as agreeable. In pathologic old age, senility
is premature and is a disease. The seat of the disease may
be anywhere or may be due to bacterial infection.
In natural death, we die by inches. But while there is only
one path by which we may enter the world, as Pearl points
out in his remarkable book on Death, there are many that
lead to the River Styx. Death does not strike at random, but
in an orderly way; and there are many ways of dying. We
die when an essential part of our body breaks down.
From an analysis of the mortality tables of England and
Wales, the United States, and Sao Paulo, Brazil, Pearl found
that over half the deaths in all three countries are due to
faulty wind and food canals. While both canals are inside
the body, they come in contact with air, food, and water from
the outside. The skin also is exposed to the world, but it is
armorplate against foreign invasion. Wind and food canals
have no such protecting layer of pavement cells as has the
skin. Outer skin and lining of wind and food canals con-
stitute the body's first line of defense against invasion of
bacteria.
The next chief cause of death is the circulatory system;
the blood is the body's second line of defense. When the
first fails to check the enemy, the way to the blood is open.
Hence the great part played by the circulatory system as the
second great cause of death. As Pearl says, we should live
much longer if our lungs were as good as our heart.
The death rates show certain important age and sex fluctu-
252
THE ENDOCRIiNE GLANDS AND THE CAUSES OF DEATH
ations. Early infancy deaths are heavy. There is then a
sharp drop until the 10-15-year period, when the rate begins
to rise to the 20-25-year period. Thereafter the rate rises
slowly until the 50-55-year period, when it begins to rise
again rapidly.
The death rate from failure of circulatory system rises
steadily from maturity until the eighty- fifth year, when it
slows down. But between the fifth and thirty-fifth years this
rate is higher in females than in males, presumably because
the changes accompanying puberty are graver. Up to the
sixty-fifth year deaths from breakdown of the sex apparatus
are also much greater in females.
The chief cause of death among males during the first year
is from the food canal; after that, to the sixtieth year, the
respiratory system; after the sixtieth year, the circulatory
system.
Nearly 60 per cent of the deaths were from organs derived
from the endoderm or inner germ-layer — the layer that orig-
inally was outside the body. In the developing embryo that
layer comes to be folded within the body and lines the food
canal and accessory organs of digestion. It is an old-fash-
ioned, out-of-date relic of antediluvian ectoderm. As a lining
for the food canal it is our weakest spot.
Our strongest spots are the skin cover of our body and our
nervous system. Both are derived from the ectoderm or
outer germ-layer. Deaths from structures derived from this
layer make up only about 10 per cent of the total. Almost
no germs get through a healthy skin. The cells of skin and
nerves have differentiated most from their primitive structure.
The remaining 30 per cent of deaths are from the meso-
derm or middle germ-layer, circulatory and urogenital
systems and muscles. The breakdown of the female repro-
ductive organs is also a heavy factor in infant mortality.
While mortality due to breakdown in ectoderm organs is
about the same for the two sexes, female mortality from
253
WHY WE BEHAVE LIKE HUMAN BEINGS
mesoderm is as great as from endoderm breakdown twenty
years before it is in males.
Death comes, then, according to Pearl, because our bodies
are made up of systems specialized in structure and function.
In becoming specialized, their cells have become so differ-
entiated that they have lost the power of indefinite and inde-
pendent existence. Thus the cells lining our lungs can be
nourished only if the cells of the food tract and the blood
keep on the job. Some systems are better made than others.
The brain outwears the heart, the heart outwears the lungs.
The striking agreement as to the causes of death which
Pearl finds in such dissimilar countries as England, the
United States, and Sao Paulo, force him to conclude that
innate constitutional factors, along with environmental
factors, largely determine rates of human mortality. In cer-
tain diseases, of course, environment is the important
factor.
The causes of death, Pearl finds, are in the following
descending order: respiratory system; digestive system; cir-
culatory system and blood ; nervous system and sense organs ;
kidneys and related excretory organs; sex organs; skeletal
and muscular system; skin; endocrine organs. Or, arranged
proportionately according to embryonic germ-layer origin:
endoderm diseases 5.2 and mesoderm diseases 3.8 times
those of ectoderm origin.
We may be as old as our arteries — and so no good for
digging a sewer; but we are also as young as our brains —
and so, good where brains are needed. But when any vital
system breaks down, the machine stops and we are dead.
19
Medical authorities believe they could add thirteen years
to life if given full control in cases where death could reason-
ably be prevented. A better life insurance is to pick parents
who will live to be eighty; they will give you a twenty-year
254
THE ENDOCRINE GLANDS AND THE CAUSES OF DEATH
better hope of longevity than parents who will die under
sixty. They are the best life insurance.
Why not? Each group of animals has its normal span
of life. Also man. Human beings vary; most of their
specific characters are inherited. Longevity is a specific
character, longevity also is inherited.
Those who live to great age as a rule are children of
parents who lived to great age. If one cannot choose both
parents who will live to old age, it is better to choose a long-
lived father than a long-lived mother. Four per cent more
children lived to be eighty where the father, but not the
mother, lived to be eighty, than where the opposite condition
prevailed.
Karl Pearson concluded from a study of the life span of
brothers that environment is not the important factor in
longevity; also, that from one-half to three-fourths of deaths
are predetermined at birth by inheritance factors. This con-
clusion has never been advertised by health resorts or elixir
manufacturers.
Death rates and life spans are but two phases of the prob-
lem of longevity. If environment — including health resorts,
elixirs, poverty, and bacteria — is not the factor in death
rates, it cannot be the factor in the life span.
From one-half to three-fourths of the death rate is selec-
tion: death comes when one has used up one's inherited
capacity for life. Adults of sound body are more likely to
leave offspring than those of weak; their children are more
likely to survive. Weaklings may survive to maturity, their
children are less likely to survive.
Hence the high infant death rate in the first two years;
the unfit are weeded out. Natural Selection is still at work;
it has always been at work. This rate is especially high
among children of unsound parents. Hygiene and prevention
lower the rate during these two dangerous years — ^prolonging
lives to succumb at a later but early stage.
A banana fly of ninety days is as old as a man of ninety
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WHY WE BEHAVE LIKE HUMAN BEINGS
years. Twenty-four hours after emerging from the pupa
stage, the female fly lays eggs. These in one day become
larvae, pupae three days later, adults five days later; ten days
to a generation. Pearl tested the life-span inheritance theory
on these flies. More females than males survived — as in
man. The only fly that lived to be eighty-one days old was a
female. Long-lived parents bred off'spring that lived long.
Pearson was right: duration of life is an inherited character.
How about germs of diphtheria, tuberculosis, etc.? Loeb
tested this on flies, with the surprising result that those kept
free from bacteria were possibly shorter-lived than germ-
laden flies, certainly no longer. The experiments indicated
"that higher organisms must die from internal causes even
if all chances of infection and all accidents are excluded."
We are never without bacteria; we could not live without
them; there is no habitable spot on earth free of them. Of
humans who have reached the thirty-fifth year, 95 per cent
have been infected at one time or another with the bacillus
of tuberculosis ; in less than one in ten does it become active.
Death rates in the poverty lanes of Paris and London do
not tally. In Paris the excess death rate in the poorest as
against the richest quarter is 104 per cent; in London, only
30. The lowest death rate in London is not in the richest
quarter. The real influence of poverty on death rates could
only be determined by transposing the inhabitants of the two
groups and comparing rates. The "poor" of Paris and
London are not necessarily biologically poor.
It is the pace that kills. "General Sherman," the giant
redwood, was killed at the age of 2,171 years. He was a
seedling in 271 B. C. He never knew what hurry meant.
Nor did the tortoise that lived 350 years. The faster we
live, the sooner we live life up. Rate of living is a factor
in longevity. Slonacker tested this on rats. He put four in
squirrel cages and let them race. The average life span of
the marathoners was 29.5 months; one lived thirty-four
months and ran 5,447 miles. Three other rats were reared
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THE ENDOCRINE GLANDS AND THE CAUSES OF DEATH
in squirrel cages, but were not permitted to race; their
average span was 48.3 months.
Loeb tried flies. Cold makes flies sluggish; those at cold
temperature lived longer than those at high. At 86 degrees,
his flies lived 21 days; at 68 degrees, 54 days; at 60 degrees,
124 days. From which he inferred that if we could keep
our blood temperature at about 45 degrees, we might hope
to live about 1,900 years. But life would be at a low level!
Unfortunately, our early ancestors left no trustworthy vital
statistics. But from trustworthy inferential data there is
reason to believe, as we might expect on purely biologic
grounds, that longevity is on the increase. At least, life
expectancy has improved during the last 2,000 years. Of
100 Romans born in Egypt in the days of the Empire, only
9 could expect to live 68 years. Of 100 English alive at
10, 39 live to be 68. Women especially had less expectancy
of life in Roman days than now — they were in luck to be
alive at 25. But a Roman of 78 years was a better risk than
an American of the same age; a Roman had to be very hardy
to live beyond 70. In America, many weaklings are carried
up to 60; beyond that age their expectancy rapidly
diminishes.
From which we conclude that modern environment is
better for man, or that man is fitter for modern environment.
20
Life goes on: only individuals die. Some individuals
apparently are also endowed with immortality — such are the
Protozoa or one-cell organisms. Nearly all Metazoa or
many-cell organisms die — their endowment is mortal.
Man also is a Metazoon. All men die. Must they die?
Until recently this would have been a foolish question. It
cannot yet be answered, but experiments now going on for
twenty- five years give us food for thought.
Since boys have been boys it has been known that the
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WHY WE BEHAVE LIKE HUMAN BEINGS
snake's tail does not die until the sun goes down. For ages
it has been well known that many animals have the power
to grow certain missing parts. A fish-worm cut in two grows
into two worms — the head grows a tail, the tail a head. Cut
a crab's eye from its stack, it grows another eye just as good.
Cut a leg from a crayfish, it grows another leg. Cut a finger
off the human hand ; no finger grows on. But our hair keeps
on growing; it may grow even after the last heartbeat. Cut
a nerve fiber of a finger; the fiber "dies" from the point
where cut to the end of the finger and so paralyzes that end
of the finger. But the live end begins to grow again and
finally reaches the end of the finger. Even though the finger
had been mangled, the nerve finds its way, if it has to go
around bone and muscle. At the end of its journey it stops
growing; the finger is no longer paralyzed.
In 1907 Leo Loeb informed the world that he was growing
frog nerve in a glass jar. Biologists began to grow pieces of
tissue from other animals in glass jars. Wilson chopped up
a sponge and squeezed the pieces through close-woven cloth
to separate its cells. He "cultivated" one cell; it grew into
a whole sponge. Carrel cultivates all sorts of adult tissue
in glass jars; even cancer cells. He has cancer cells that
have outlived several hosts. He cut a piece from the embryo
of a chick; after nine years it was still alive and growing.
He cut muscle cells from a chick embryo's heart; they grow
and beat.
That opened the coffin again. Tissues cut from living
bodies, it was thought, should not grow, they should die!
They are not ger/Ti-cells, they are only body or 5077ia-cells.
Soma cells were not supposed to be endowed with immor-
tality. Yet under cultivation they live, they multiply, they
grow. In a jar.
Soma cells also are potentially immortal!
Then why do they die? Why is our saliva full of dead
cells and the skin of our body covered with dead cells? WTiy
is the body that was living now dead?
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THE ENDOCRINE GLANDS AND THE CAUSES OF DEATH
What is death? No one yet knows. No one knows what
life is. We only know the living from the dead. We know
more about the causes of death than we did. But are we
checking disease, postponing death? Can we renew our
youth? Are we about to make death merely an accident?
Can we synthesize life? Man by nature is not too modest,
nor by training without hope or the habit of stretching his
imagination. Our answer, then, is, "Yes, why not?" And
a pleasant time is had by all. Molasses catches more flies
than vinegar.
Such important functions of our body as heartbeat, breath-
ing, digestion, and absorption are beyond the control of our
wills; they have their own centers or systems of control. We
do not even yet know where all these centers and systems
of control are located.
When we know just what takes place when a sweet becomes
a sour, or how a cell converts sugar into glycogen, or why
a heart beats in a certain solution and stops dead if the
acidity of that solution is increased by one billionth part, we
can begin to talk about prolonging life.
Not one single process that goes on in any one cell of our
body has yet been completely analyzed. When some of the
processes of life have been even fairly well analyzed, it will
be possible to speak of the artificial synthesis of life.
Nevertheless, there is every reason to believe that we may
look forward to a greatly increased control over evolutionary
processes. Why not? Think of the already enormously
increased ability to control growth in living organisms. This
control has only come with an understanding of the nature
of the stuff of organisms in which energy is transformed, and
of the relation of organisms to the external world. With
wider understanding will come wider control. But progress
must be slow, because, as Child warns us, we deal with
internal conditions which are the result of millions of years
of alternating change.
It is all so new. There are to-day a half-dozen flourishing
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WHY WE BEHAVE LIKE HUMAN BEINGS
sciences devoted to the study of life where a few years ago
there was not one. For the first time in human history man
has trained his new-found instruments of precision on newly
conceived problems. He can at last ask questions about
himself and about life in general. Direct questioning has
replaced vague and childish speculation. Problems have
been formulated and solved. And every problem solved has
opened wider vistas — and more problems. But no problem
was ever solved by propaganda. Nor is disease checked by
mere optimism — though digestion can be checked by a bill
collector and a mouse's heartbeat increased from 175 to 600
per minute by a mouse trap.
The death rate is declining; it has been declining for
centuries. Men born to-day can expect longer life than men
born twenty, fifty, five hundred, or five thousand years ago.
Why this is so is not at all well understood. The decline in
death rate in modern times is as true of "backward" countries
as it is of Germany, England, the United States. The drop
is also as true of the non-preventable diseases as of those
which are supposed to be subject to control.
The part that health officers, etc., play in this decline is
uncertain. War has been increasingly waged against tuber-
culosis for nearly a century; the tuberculosis rate has dropped
less than that for diphtheria, croup, typhoid, and dysentery.
The cause of many diseases is yet unknown, of others only
partially surmised. Man responds to his environment, as
does all life; but he is changing his environment, in places at
an extraordinarily rapid rate. What is the result or what
will be the result of these changes is not yet known, nor can it
be predicted with any degree of certainty.
We hand public health, as we do government, over to a
power which we expect thereafter to run of its own accord.
But neither ever gets very far ahead of the load it is supposed
to carry. Meanwhile, for every one that knows what to eat
and why, there are a hundred who eat for their tongue's sake
and let it go at that, not knowing that a double chin may be
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THE ENDOCRINE GLANDS AND THE CAUSES OF DEATH
a misdemeanor or that arteries and nerves may be as easily
choked in fat as a cat with butter. Many use their body as
a clothes horse and are only concerned with the parts that
show.
Startling facts come from physiological laboratories. They
force us to revise our conceptions of life and death, of youth
and old age. All protoplasm is potentially immortal. Man
is protoplasm. Hence . . . But Man is highly complex pro-
toplasm— an organism of infinite complexity, of tissues and
organs and systems greatly differentiated, some more, some
less. This mass of protoplasm functions, lives, because these
parts work together for a common end. They are marvel-
ously balanced. Upset the balance: disease; if the balance
cannot be restored, the machine is broken. A few minor parts
may be restored; a few may be dispensed with. The machine
breaks when a vital part breaks. It never runs again.
Isolate the liver or one brain cell and study it a lifetime:
liver as function and cell as behavior are as meaningless and
as lifeless as a last year's bird nest. The parts of the human
body are meaningless in and by themselves. Put some cells
in a glass jar and watch them grow. Where does this land
us? Those cells are immortal — in "proper medium."
Each of the billions of cells in the human body must also
be kept in proper medium. Those cells themselves are the
medium. On their own shoulders rests the burden of keeping
that medium proper; they and they alone can right the
machine, they and they alone know the levers. If they can-
not reverse, there comes a crash. The machine is broken.
Nothing yet has come from the laboratory to give us hope
that the crash is not inevitable. All vital processes are re-
versible; they must be. To live is to keep making compen-
sations: changes, backward and forward. Simple organisms
have it in themselves to make these compensations; they have
their dynamic equilibrium in their own hands, as it were.
Man does not: it is the price he pays for hands. Hands
wear out. Even brain cells. We cannot grow new hands
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WHY WE BEHAVE LIKE HUMAN BEINGS
or new brains. They grow up together, though of different
heritage, the brain being far more ancient, hence more en-
during. They live together: a pin-prick on the finger may
be the death of the brain.
The break may come from within, or from without, or from
any one of a vast number of causes. Three out, all out. So
in the game of life. The number of our outs — or innings —
is set in our inheritance and buried from sight in the complex
mechanism which is ours for a while. We can burn it up or
jolly it along. But beyond a certain point there seems to
come a limit to its mileage. The machine wears out because
it is that kind of a machine. It dies because sooner or later
the Marksman of Death strikes a vital spot.
Pearson in his Chances of Death pictures a Bridge of Life
across which is a trickle of humanity. They are under the
fire of the five Marksmen, one for each Age. They fire with
different weapons, speeds, and degrees of precision. The
first Marksman concentrates a deadly fire upon Infancy —
before as well as after birth; "beating down young lives with
the bones of their ancestors." The second Marksman aims
a machine-gun at Childhood; his fire is concentrated, the
loss is less appalling. The third shoots at Youth with a bow
and arrow; there is no great loss. The fourth fires slowly at
Maturity with a blunderbuss; his hits are scattered. The
fifth Marksman of Death is a sharpshooter; no one can escape
the Death of Senility.
262
CHAPTER V
THE INTEGRATING ORGAN AND MECHANISM OF ADJUSTMENT
I. The Old and the New Psychology. 2. The Impulse to Live. 3. Samples
of Low Life Behavior. 4. The Animal "Mind." 5. The Excitability of Living
Matter. 6. The Nature of the Reflex Arc. 7. The "AU-or-None" Conductors.
8. Reflex Action. 9. The Nature of Nerves. 10. The World as Stimulus.
II. Receptors of Sights and Sounds. 12. Receptors of Chemical Stimuli,
13. Visceral and Kinesthetic Receptors. 14. The Nervous System. 15. The
Lower Centers of the Nervous System. 16. The Supreme Adjustor. 17. The
Pictured Movements of the Brain. 18. The Conditioned Reflex. 19. The
Autonomic Nervous System. 20. Cramps and Fatigue. 21. Mind and
Consciousness.
1
Of all the 'ologies I studied in school, the one that gave me
the least light on man and myself was psychology — excepting,
possibly, mineralogy. It worried me : I wanted to learn about
my own and man's psyche, and did not. I assumed it was
because the course was over my head. It was.
For this reason. To the old psychology heads were like
crystals. By gazing into them, called "introspection," the
mind could be seen and studied. Crystal-gazing never did
call itself a science; mind-gazing did, but is now also only a
cult. The introspectors could not agree as to what they saw.
But that they were looking at "mind" they had no doubt.
Their logic was simple and convincing: mind is not matter,
the body is matter; mind and body, therefore, are separate
and distinct entities. They turned the body over to sawbones
and kept "mind" for themselves and went on arguing about
what they saw in it.
"I see red," says one. "Is it pure?" asks another; "is it
perception, sensation, connotation, or ideation; or is it a
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WHY WE BEHAVE LIKE HUMAN BEINGS
conception, or the imagination? Is it as content, awareness,
or as ego? If as ego, can you time it; if as awareness, can
you weigh it?" This is all nonsense, of course; but not more
so than the psychology I studied in school.
The net result of introspection was a Noah's Ark of stalls
each labeled for an occupant, a "content of the mind." It
was not unlike the shaved-head phrenology charts with allotted
areas for bumps of amativeness, adhesiveness, philoprogeni-
tiveness, and other faculties. Phrenology broke down before
the fact that my bump of "amativeness" may be due to a
thick skull, water beneath the skull, or the fact that with no
bump at all I am very amative.
The old psychology went the same way. Mind was found
to be neither a "secretion of the brain" as bile is of the liver,
nor any thing or process apart from a living body. It was
next discovered that the brain itself is simply a part of the
central nervous system, the body's integrating organ or
mechanism of adjustment. That this mechanism is born
primed for many primitive naked-and-unashamed activities,
but is unlearned in modern ways and learns only by expe-
rience, was the next step in the downfall of the old ps)^-
chology.
With the realization that some individuals have no mind at
all, individual behavior began to be a problem. With the
realization that the outstanding fact of evolution is individual
variation, and that the significant fact of the genus Homo is
individual behavior, and that stereotyped behavior in an in-
dividual is a sign of abnormality and if vicious lands him
in a padded cell, the old science of mind-gazing lost its pep
and the gazers began to try to find out what happens to human
beings and why. And that is a real problem, from the com-
plete solution of which we are yet miles and years.
To solve a problem is to know its laws. To know the laws
is to be able to make predictions. For example: I can pre-
dict the behavior of a pint of ethyl-alcohol under many physi-
cal and chemical changes so accurately that you can expect
264
THE MECHANISM OF ADJUSTMENT
your pint of C2H5OH to behave the same way under the same
conditions. That is science. I cannot predict your behavior
when you drink that pint of alcohol — the personal equation
is too big.
Sciences are exact to the extent that the personal equation
is eliminated. The personal equation can never be eliminated
in predicting human behavior.
General predictions, yes. Cats are cats, dogs are dogs,
pigs are pigs. No two alike, but enough alike for practical
purposes. Can you predict any certain tomcat's behavior
an hour hence? You cannot even predict next week's weather.
A three-year-old child contains more elements than the
weather and is driven by more forces. Can you predict its
behavior? The particular behavior of any one human being
under any one certain condition may depend on an infinitesi-
mal amount of a hormone yet unknown to science. Give up?
No ; look into hormones, into individual inheritance, into mil-
lions of reflexes many of which may be put out of action by
the wink of an eye. What is the nature of hormones, what is
it that is inherited, how are reflexes conditioned and acquired,
how are they put out of action, why can a wink be so devas-
tating?
Man both makes and outlaws his own laws. He cuts off"
his nose to spite his face; dies to live and makes a martyr of
himself in the name of custom; scarifies his face and body,
deforms his head, waist, and feet, and wears sackcloth and
ashes, patent-leather shoes, and plug hats in the name of
fashion; and consigns to hell his infants' souls in the name of
the Saviour he implores to save his own soul.
The vagaries of human behavior seem as countless as the
sands of the sea; but the sands can be classified and described.
Human behavior also, though the problem is more complex
and shifting. That man makes an ass of himself and elects
himself a saint only adds zest to the study of human behavior.
Man is not only the most curious thing in the world, but the
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WHY WE BEHAVE LIKE HUMAN BEINGS
most interesting, not only to live with, but as an object of
observation.
The old psychology died hard ; it has not been easy to give
up mental faculties. But in surrendering mind to philosophy
we have gained living human beings; in abandoning the
search for some magic power to transform human nature we
have discovered how to transmute "imps into angels by the
alchemy of smiles."
Not that we are born imps, but helpless infants with a
specific nature called human and a definite equipment for
learning human and inhuman behavior. This inheritance
makes up the raw materials of the new psychology. What is
its nature, how is it modified by nurture? These two problems
resolved, the new psychology can begin to formulate the laws
and principles which govern human reactions, in individuals,
in groups, in nations. When that time comes — and it will —
it will be possible so to organize human affairs and human
society that the innate love for life can find satisfaction in
loyalty to ideals and service to humanity.
2
Everything cuts up or behaves: electrons, atoms, ions, mole-
cules, water, gunpowder, living beings, everything. We can
know things only by their behavior. Living things have their
own modes or ways of behavior; there are certain criteria of
livingness. Among these criteria is growth in a complex dy-
namic protoplasmic mechanism. Such a mechanism cannot
grow without energy. This energy comes primarily from
the sun; the earth itself is the source of the protoplasm.
The living organism thereby called to life came at last to
be born of woman. From the beginning of its individual ex-
istence as a fertilized ovum until senile decay and death
exhaust its inherited potentialities and complete its living
cycle, it never stops growing, although it does stop growing
larger. This growth or change of body during the life cycle
266
THE MECHANISM OF ADJUSTMENT
is one aspect of human Hfe: genetic behavior or morphology.
During life certain vital processes take place in glands and
organs of digestion, circulation, respiration, etc., whereby
the growth of the body is regulated and the individual is
maintained in health. This is visceral behavior.
The third aspect of behavior includes the responses where-
by the individual is adjusted to the outside world. These
responses are generally made with the motor mechanism of
the body and involve locomotion or speech, and hence are
called somatic behavior, or psychology.
But note that all forms of behavior of all living things
have a common origin, spring from a common root, and obey
the same fundamental laws of life. Hence every phase of
human behavior is but part of the problem of life in general
— and every problem of life involves all of life and the
environment of life. The uniqueness of life is the way living
beings respond to vital stimuli, thereby so adjusting them-
selves that they continue their existence as living beings.
Therein lies the uniqueness of life. To say, with Herbert
Spencer, that life corresponds with environment is, as Herrick
points out, to advance life no further than a self -registering
thermometer. The thermometer reacts to an outside stimulus;
the stimulus is an impinging energy. But life not only wars
against disintegrating agents, "it captures the attacking forces,
appropriates their base of supplies, and compels the hostile
phalanx actually to turn about and fight the battles of the tri-
umphant organism."
Why this unique behavior of living things? It is their
nature; that kind of behavior is inherent in living protoplasm.
Because of its nature, it adjusts itself to its environment.
It eats, it excretes; it derives energy from food, it is driven
by energies which impinge upon its body. Some of that
energy is dissipated in heat and in energy-consuming activities
inside its body; some of that energy is stored within its body;
some of that energy is expended in waiting for or going after
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WHY WE BEHAVE LIKE HUMAN BEINGS
more energy. These are all vital processes and consume
energy for vital adjustments.
"Vital" is a useful word and cloaks much that is yet in-
scrutable. But the energy with which you hold this book is
but the energy of your impinging environment so combined
with the energy within you — orginally won from nature by
plants — and so transformed in you into such a high potential
current that it can be made to do such work as human
machines are by their nature and training impelled to do.
Living impulses, vital adjustments; the call to live, the
response to the call; the living being as an individual; the
reactions of the individual living human being: these matters
are now our concern. But again let it be said that any
psycho-analysis which neglects the facts of genetic and vis-
ceral behavior will never discover the materials with which
to synthesize a human being. Human psychology is rooted in
living human protoplasm and can be explained only in terms
of its antecedent history.
3
The pyschology of bacteria is not well known because they
have only recently been discovered. But the lowest-lived
bacteria known to the microscope make distinctions that
baffle the biochemists who study them. They have an astound-
ing capacity to transform energy and they are sensitive to
extraordinarily minute stimuli. Their behavior can only be
described in physico-chemical terms.
Some bacteria produce light. Do they burn luciferin?
Do they use the enzyme lucif erase as catalyzer? Fireflies do,
and have special organs for its manufacture. These organs
are controlled by nerves and respond to certain stimuli; and
they all light up at once! Firefly behavior can be talked about
in psychologic terms, but such terms tell us nothing of the life-
light of the light-producing bacteria that cause decaying wood
and flesh to glow. The psyche of bacteria is physics.
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THE MECHANISM OF ADJUSTMENT
Animals are fond of sugar. There are hundreds of sugars;
some are so much alike that man cannot tell which is which.
Bacteria can. They can detect a thousandth part of 1 per
cent of certain sugars; they prove it by their behavior. Are
they on speaking terms with atoms? At any rate, their reac-
tions are more refined than those of the sugar chemist's re-
agents. And yet bacteria are so low that science has not yet
decided that they are real cells. But they are alive; they re-
spond to stimuli and run the gamut of adjustment behavior
on which life depends.
Animal adjustment generally involves locomotion. Low
forms flow, because life is fluid. The solidity of bones,
horns, teeth, hair, etc., is due to dead mineral matter between
living cells, as is the "wood" of trees. White blood-cells
flow through membrane. Certain Protozoa that live on moldy
wood can flow through cotton mesh so fine as to strain the
food from their body. Once through, the streams of proto-
plasm unite again into a single body which behaves as though
it had not been strained. By such streaming movements
amebae and white blood-cells ingest food particles by flowing
around them.
A worm has been seen under the microscope to swim
through the protoplasm of a frog's muscle, the protoplasm
closing behind the worm. At one point the frog's muscle
had been injured — it was "dead"; the worm could not swim
through that, it went around it as though it were a stone.
Because of this fluidity, living protoplasm can respond.
Without fluidity, muscles could make no response. Cutting
a nerve paralyzes a muscle but does not kill it, though disuse
will cause it to waste away. Every living muscle-cell can
respond to stimulus.
The microscopic cilia lining our windpipe move in defi-
nite rhythmic sequence, wave after wave, like a field of wav-
ing grain. A speck of dust excites them to move; the larger
the speck, the faster they move. Cilia are ancient structures,
the sole motor mechanism of many micro-organisms. Could
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WHY WE BEHAVE LIKE HUMAN BEINGS
we get as much work out of our motor apparatus as the little
Paramecium does with its cilia, we could lift 1,500 pounds.
Cilia cut from a frog's throat keep right on moving; they
will work a weight uphill.
Bacteria, amebse, white blood-cells, muscle-cells, ciliated
cells, are all types of behavior, samples of life's adjustments
to livable conditions. Every living cell and every living or-
ganism, from yeast to man, has its own reaction system, its
own type of behavior; its own psyche — if you like that word.
4
Washburn's Animal Mind, second edition, lists 841 titles
consulted in the preparation of her book. That was eight
years ago. The next edition will probably list a thousand
titles; shall we know more then about the "mind" of animals?
Can the mind be seen? Why not. We "see" metabolism,
and know much of the processes of chemical exchange be-
tween living organisms and their environment. We call these
exchanges physiological processes; and while there are many
that are only partly understood, and many that are as yet
only partially guessed at, no one speaks of physiological
processes with furrowed brow, unless, indeed, the process
at the time is functioning badly. But "mind" suggests mys-
teries, vague realms in which souls converse with souls and
psychic phenomena defy every known or conceivable law of
matter and energy.
Mind is not matter; neither is the attraction of the positive
half of the magnet for molecules of potassium and sodium,
matter. But the attraction of an anode for potassium and
iron filings is a relation between matter. Certain elements
are attracted by an anode, some are repelled; a youth is
attracted by a maiden. There the matter is; it is open to in-
vestigation. The "matter" may be a wisp of hair or a down-
cast eye.
Mind is like life: it is known only by the company it keeps,
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THE MECHANISM OF ADJUSTMENT
living organisms; they are real. There are criteria for liv-
ingness. They often fail. An organism may show no signs
of life: as an opossum, or a grain of wheat. Is it alive?
Only by applying certain stimuli can we tell. If it makes no
response, it is dead. "Certain stimuli": what? Stimuli known
to be harmful to opossum or vital for wheat germs.
The live grain germinates under proper stimuli. Its be-
havior can be observed and described in terms of energy and
matter, and in its behavior will be found no contradiction to
the laws of physics and chemistry. That germinating grain
shows behavior; it has no mind, of course? Plant physiolo-
gists are not so certain; some are quite certain that if an
ameba has a "mind," a grain of wheat has.
Has the ameba a mind? But, first, what is mind: con-
sciousness? reason? intelligence? intellectual faculties? Or
all these combined? I may think I know what is on my mind
and what my mind is. How can I know your mind? I look
at a picture: I know what I see; I know the emotions, mem-
ories, etc., the picture rouses in me. I cannot know what that
picture is to you except by your behavior : words, actions, etc.
Even then I must interpret your behavior in terms of my
own experience. There may be nothing in my experience
which gives me a clue to your behavior.
When Washburn says that we know that consciousness —
"as evidence of mind" — resides in ourselves, that it undoubt-
edly exists in animals with structures resembling ours, and
that "beyond this point, for all we know, it may exist in
simpler and simpler forms until we reach the very lowest of
living beings," I do not see that she has moved either forward
or backward. To say even that mind is a quality of living-
ness, a sign of life — as is oxidation a sign of metabolism —
is probably quite as futile. To say that one ameba engulf-
ing another is a sign of hunger, a spitfire cat with an arched
back and slashing tail a sign of anger, a dog with a can tied
to its tail yelping down the street a sign of fear, and a strutting
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WHY WE BEHAVE LIKE HUMAN BEINGS
cock a sign of amorousness, is to anthropomorphize animal
behavior.
Mental states, yes ; we have names for dozens of them. I
know how I feel when I am kicked and I have names for my
feelings. I do not know how a kicked dog feels. I can
judge only by his behavior. He might wag his tail and appear
to like it. I could then only understand his behavior by know-
ing his history: the kick might be an invitation to a fox-hunt.
Mind, like life itself, is quantitative. I stretch my arms, a
button pops off my vest. I decide to change my tailor, or
reduce, or have the button sewed on in the morning, or sew it
on myself. I do nothing. Another button pops. Now what?
The ameba has no buttons to worry about. Sound and
sight of buttons never enter its mind. The stimuli which
beat upon it from the time it is pried or kicked loose from
another ameba until it loses its own identity by dividing into
two amebae are not such as beat upon the near-by frog that
is now calling its mate.
We cannot know how the world looks to the ameba. But
we can put questions to it: what do you think of red ink —
do you like it, can you digest it, do you want more? How
does it feel to be turned loose in a drop of water, with nothing
to stand on or hang to? Such questions are put to amebae and
to other living creatures. These questions are in terms of
physical and chemical change in environment. By their
behavior under changed conditions inferences are drawn as
to their mind.
But the ameba's mind must be of a different quantity from
ours. We "smell" and "taste" food. Can it distinguish
brickdust from protoplasmic dust by smell and taste? It can
make the distinction — and does, without visible structure of
taste or olfactory organs.
By its behavior we know that the ameba distinguishes and
that in certain ways it makes finer discriminations than we
do. Whatever its senses, we can only say they are appro-
priate to its needs.
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THE MECHANISM OF ADJUSTMENT
When Jennings says that the ameba "reacts to all classes of
stimuli to which higher animals react," he simply bears
testimony to an inherent criterion of living organisms: a
certain kind of reaction system. By that system they main-
tain a certain dynamic equilibrium and thereby adjust them-
selves to stimuli destructive of and favorable to life. If
that system fails, they lose their minds — as does a drop of
vrater when an electric current passes through it.
In other words, it is time to give the mind a rest. The
loose use of the word has probably done more to befog think-
ing than any other word, except possibly "unconscious." It
means so much it means nothing. By using it in connection
with animal behavior it implies some transcendental mystery
in living organisms. There is much ignorance among human
beings as to the nature of human beings — so much, in fact,
that it borders on the mysterious; but the mystery of a sand
dune, of a snow crystal, of a flash of lightning, and of an
am.eba's response to a lump of sugar or a bull's to a red rag,
is all of the same order. To identify mind with protoplasm
or with nervous action is to talk about a hole in the ether or
disembodied spirits. This is not a static world, and matter
will cut up as long as the sun shines. When matter is as
complex and has had as much experience as has the stuff of
which we are made, it seems inevitable that it should have
a vast capacity to vary its behavior in response to the situa-
tion in which it finds itself. It can do this because it is irri-
table. When it can no longer get excited about certain things,
it is finished as protoplasm. If you still insist on mind, call
it a manifestation of the kind of excitability that inheres in
all dynamically active protein compounds called living
beings.
Meanwhile, we shall do well to recognize, with Herrick,
that the real problems of human psychology are still over our
head and that the problems of animal psychology are pro-
portionately difficult as their sensori-motor organization
diff'ers from ours. "The popular dramatization of animal
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WHY WE BEHAVE LIKE HUMAN BEINGS
life and imputation to them of human thoughts and feelings
may have a certain justification for literary or pedagogic
purposes, the same as other fairy stories. But let it not be
forgotten that this is fiction for children, not science nor the
foundation of science."
5
The microscope reveals no nerves in the ameba. But the
ameba has curiosity: it explores its world, even though that
world is less than a drop of water. The ameba is an individ-
ual, as was Socrates, or as you and I are. Socrates was
condemned to death for corrupting the morals of the youth!
He had irritated some of the best minds.
All life is irritable. This irritability inheres in every liv-
ing cell of every living body. Because of that quality the
ameba is excited to explore its world and man his. That
quality leads to the ego in the individual and to culture in
the human race.
The enemies of Socrates were so excited that they put him
to death. Hunger can so excite an ameba that it commits
cannibalism. Moisture and heat so excite a grain of wheat
that it sprouts; if it does not respond to sprouting stimuli, it
is dead. An ameba beyond the stage of excitability is dead.
Irritability is in the nature of living things, regardless of
size and shape, whether plant or animal, one-celled or many-
celled, and of every cell in every living body. Because of this
irritability, life responds. An ameba responds to hunger
by pursuit and capture. These actions are responses, reac-
tions. My response to fried chicken may be a smile, mouth
water, and activity in the mastication mechanism. My re-
sponse to fried chicken half an hour later may be a sickly
grin; I do not want to think of food. The ameba acts the
same way after a hearty meal.
Without excitability there could be no response to physical
or chemical change in environment. Any change in the en-
274
THE MECHANISM OF ADJUSTMENT
vironment which causes excitation is a stimulus. Environ-
ment is a big word and covers all outdoors and all our insides,
including toothache and an idle thought ; the kind and degree
of change which serves as stimulus depend on the organism.
Man's is infinitely complex because he can store experience
and vary or delay reactions and because he can respond with
words as well as with more overt action.
A baby cries in the next room; my response to that stimulus
may be words, or a bottle, or any one of many possible re-
sponses. The response I make will depend on a lifetime's
accumulation of stimuli and reactions.
Our brain itself and our wonderful special sense organs
are rooted in the nature of living things to maintain their
dynamic equilibrium by appropriate reactions to vital stimuli.
When we cannot do this, we are dead as a door nail.
Nails react to chemical and physical change, but their re-
actions are because of the elements in them and not because
they are nails. Iron may enter the ameba's soul; its reaction
is not that of elements to elements, but as a complex reaction-
system. With that it can respond by appropriate action to
such stimuli as would leave the nail unchanged for a million
years, or flee from an acid that would dissolve the nail in a
few moments. The nail is irritable; but there is no sign of
organization in its responses. Nor can it reproduce itself,
nor perform the functions of metabolism, nor go in out of the
rain. It cannot adjust itself to its environment; life can, be-
cause it has an adjusting mechanism.
Living protoplasm has the power of adjustment. Our
nervous system is our visible mechanism of adjustment. It
is new in life, as are skeleton and intestine; but new only as
a new contrivance for doing something that has been done
throughout life. The automobile is a new contrivance for
getting about, but living organisms got about before there
were automobiles — or legs, or wings, or fins; and adjusted
themselves to their environment before there were nerves or
intestines.
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WHY WE BEHAVE LIKE HUMAN BEINGS
The microscope shows no behavior mechanism in an egg-
cell. But a pin-prick in the membrane of that cell causes it
to vary its behavior: it dies. That same pin-prick in another
egg-cell may start it on a road which ends with a frog. Is
this "behavior" or "metabolism," psychology or physiology?
Once it would have been called black magic, and Loeb, the
man who did it, would have been hanged — or made high
priest.
To-day the man who describes one ameba chasing another
calls himself a psychologist; the man who describes what
happens to the ameba that is caught calls himself a physiolo-
gist. Yet chase and digestion are two aspects of the same
problem: why protoplasm and man go to war. In other
words the fundamental difference between physiology and
psychology is precisely nil.
In chase and digestion the ameba reacted, behaved. It
moved: it has power of locomotion. Its movements were
purposive. It persisted. It tried and tried again. And does
other tricks which are black magic unless we assume that the
lowly ameba is in all essential respects organized for life.
It is the inherent character of excitability that comes at last to
be expressed in nerves. Nerves are late in life, excitability
began with life.
A flea bites an elephant's tail. The flea-bite is a stimulus.
The stimulus excites — what? The tail? No; the elephant.
The elephant is annoyed and decides to lash its tail to shake
the flea off". The fact that the stimulus led to action implies
more than mere irritability. The stimulus was transmitted
across many feet of elephant body. That implies a conduction
system.
The ameba is not so large. The space a stimulus must
traverse across its body is measured with a microscope. But
the stimulus is conducted across its body as it is the length of
the elephant's body. Protoplasm is so organized that an ex-
citing stimulus can be transmitted throughout its body. It
276
THE MECHANISM OF ADJUSTMENT
responds as an individual and thereby adjusts itself to its
environment.
It is the excitation-conduction system of living organisms
which makes adjustment possible. That system began with
the lowest form of life, it is as old as life itself. It grew more
complex as the organism became more complex. It led finally
to special organs for receiving stimuli, special wires for con-
ducting stimuli, and special motor machinery for reactions
according to the needs of the organism as a whole for ad-
justment.
Excitation, as Child points out, is the great energy-liberat-
ing process; it leads to faster living. In conduction, excita-
tion passes from one region to another. The dynamic change
in the excited region is the exciting factor in the adjoining
region. But both excitation and conduction are not only inde-
pendent of specific forms of life, but also of the nature of
the stimulus or external factor. Which means that the
nervous system is to be thought of in more than mere terms
of structure.
In fact, apart from teeth and bones, there is little or noth-
ing in the human body that has meaning as mere structure —
or as mere function. Structure and function are inseparable
in living organisms.
For more than 3,500 years anatomists studied blood vessels
and blood — and knew next to nothing or worse than nothing
about the marvelous river of blood which ceaselessly bathes
the myriads of living cells of the living body. Because it
does bathe these cells, carrying to them what every living cell
must have (nourishment and oxygen) and relieving them
of what every living cell must be rid of (refuse), the enor-
mously complex bodies of Man and animals above the
humblest are possible. The blood stream made integration
possible in complex bodies — such complex structures could
function as a unit; the blood made for a degree and a kind
of individuality in a complex organism otherwise impossible.
Now note: the blood transports chemical substances. But
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WHY WE BEHAVE LIKE HUMAN BEINGS
that is not enough. My feet may be ever so bountifully sup-
plied with blood and my transportation system may be doing
its work perfectly. But suppose I have stepped on a tack or
want to tell my feet to get a move on: how can my fopt
tell me about the tack or how can I tell my feet to move
faster? Here is where the nervous system comes in as co-
partner with the blood as an integrating mechanism.
The blood carries matter; what do the nerves carry — elec-
trons, charges of electricity? Possibly. At any rate, all liv-
ing protoplasm is irritable and presumably electrically sen-
sitive. Whatever it is that nerves carry, there is no doubt
as to results: physiological influences, excitatory or inhibi-
tory, are transmitted. With nerves, quick action at a distance
is possible ; a complex mechanism is knit into one going con-
cern. The nervous system is the great integrating and co-
ordinating organ. By specializing in conduction it makes
possible quick action in distant members, widely scattered
regions, multifarious organs, and diverse tissues; the entire
organism can thereby adjust as an individual.
There is nothing simple about our nervous system, nor even
of any one of its billions of component cells, but as long as we
keep in mind its nature we can make progress in under-
standing it — and that is a long step toward understanding pa,
ma, and the baby.
6
A ray of sunlight through a hole in an awning strikes me
on the brow; I do not sense it. A moment later the same
ray strikes me in the eye; now I sense it. It is a decided
stimulus. I respond, become dynamically active. I move my
chair; hundreds of muscles are involved in the adjusting re-
action. Yet if that had been a ray of tropic sun, I might
have felt it on my brow as heat; and responded with appro-
priate movements. My response in one case was called out
by a stimulus to an organ (my eye) , in the other by a stimulus
278
THE MECHANISM OF ADJUSTMENT
to a region (my skin) ; but in both responses my adjustment
was made with reference to a new relation between myself
and my environment.
A light ray falling on any part of an ameba's body is
sensed; the animal as a whole makes appropriate response.
There is a difference. I was stimulated by the light ray
only as light or only as heat. By light only when the ray
fell on an organ specialized for light: that is, for ether vibra-
tions of certain length. The ameba felt the ray as vibration,
but whether as heat or as light we do not know. What is
certain is that its entire outer surface is sensitive to ether
vibrations. Its whole outer surface, therefore, may be said
to be receptive. Through its "skin" it receives stimuli from
the outside world. Its entire exterior surface is its receptor
of stimuli.
Both ameba and man responded to the ether-wave stimulus.
This implies two additional processes. First, some means of
communication whereby the stimulus was transmitted from
exterior (skin or eye) to the body within. In man, the means
of communication was a nerve; the nerve was the conductor.
There are no nerves in the ameba ; yet the message was trans-
mitted. The response in both animals was movement — ad-
justment. This was effected in man by certain body move-
ments; also in the ameba. In man, the movements took
place through the mechanism of muscles and bones, activity
in glands, etc. This mechanism cannot be discovered in the
ameba, but by some means the body responded; the message
was carried out. The means in both animals was the ejfector.
From ameba to man is a long jump in evolution. What
evolved: what is back of man's complex nervous system and
his many complexes of behavior? Evidently some sort of
system as old as life itself and inherent in every living being.
This system implies excitability and transmission in general,
and in particular, receptor, conductor, effector. Through a
system of this pattern man and every living being make ad-
justments to environment.
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WHY WE BEHAVE LIKE HUMAN BEINGS
Through evolution this system of adjustment has developed
into certain mechanisms and methods. Man's responses are
not ameba's, nor elephant's, nor gorilla's; the environment
to which he must make adjustment is his own, his responses
are his own.
Two important points as to the nature of the nervous system
can now be seen in bold relief:
First, in spite of structural complexity the nervous system
of man and higher animals can be conceived of in terms
of conductors of messages from receptors to effectors. The
three make up the reflex arc. The arc itself is not seen as
structure in low organisms — but they react as though the
arc were present. In other words, the reflex arc is something
new as visible structure in evolution; the dynamic action
performed by the reflex arc inheres in ameba, hen's egg,
muscle cell, every living thing.
Second, the receptors in man's earliest ancestors were on
the external surface. Where else should we expect to find
them? Life adjusts to externals; it must be so organized that
it can keep in touch with externals. Man's receptors are on
or in his skin, or begin their embryological development, as
does his entire nervous system, from the outer germ-layer.
Temperature and tactile receptors are pure skin structures,
and as compared with such special sense organs as eye, ear,
and nose, are in some respects more primitive than those of
any other warm-blooded animal. But all receptors are so
located as to be exposed to the action of environment change.
As the entire outer surface of the ameba is sensitive, so
man's entire outer germ-layer is potentially nervous. But
the nervous system itself as it exists in man is simply the
final product of the evolution of the excitability-transmission
relation of living protoplasm. Its complexity in man —
especially of brain cortex — is a measure of his capacity to
escape the limitations of behavior set by the reflex arc. He
can refer his reactions to a higher court. But even reactions
280
THE MECHANISM OF ADJUSTMENT
in this higher court are based fundamentally on reflex arc
units. The reflex arc is the basis of all human behavior.
While the conception of a reflex arc in which response fol-
lows stimulus as does the ringing of a bell the pushing of a
button, is valuable, it must be understood that the simple
reflex is a "convenient abstraction," as Herrick calls it. It
is no master key to unlock the secrets of the brain. In actual
fact, "each reflex center is usually a region where more or
less complex compounding of simple reflexes is eff'ected,
where a single afferent impulse is distributed to all the
muscles necessary for the complex motor response, where an-
tagonistic impulses meet and struggle for possession of a
final common path, or some other correlation of higher order
is eff'ected."
All this does not, of course, diminish the value of the
concept of the arc as the mechanism for immediate response
in unit behavior. This unit, says Herrick, involves the follow-
ing processes: stimulus (some physical agent impinging upon
excitable protoplasm) ; excitation (eff*ect of the stimulus upon
some receptive apparatus) ; aff'erent transmission to a center
of correlation; central adjustment (whereby the aff'erent im-
pulse is transferred to an eff*erent pathway) ; eff'erent trans-
mission (to some specific peripheral or end organ of re-
sponse) ; response (in some specific eff'ector — muscle, gland,
etc.).
The possible permutations of reflex arcs which form the
bases of human behavior reach staggering figures, unnum-
bered billions. Therein rests man's capacity to learn to do
new things, to react to situations not predetermined by his
inherited structure.
7
Living beings as transformers of energy give us the clue
to the second great step in evolution and an insight into the
nature of nerves; and thereby a better understanding of the
life of man.
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WHY WE BEHAVE LIKE HUMAN BEINGS
The transformation of energy is a dynamic process. It
implies motion, movement. Movement implies force, power.
Living beings are power plants generating energy for home
consumption. They must be, because living beings must have
something to live on, raw materials to be built into living
bodies. These materials exist outside the body. They must
be captured from the outer environment and brought within
the body cavity. Within, they are inspected; what can be
used is used; the refuse is then ejected. These physiological
processes are purely material (chemical) exchange. Life
trades with the world of environment and in death balances
the account.
This material relation of living beings to environment is
only possible because life is dynamically related to environ-
ment. Living beings are so constituted that environment so
acts on them that they react. The more complicated the
organism, the higher the rate of dynamic action.
This is beautifully illustrated in the respiration rate in the
human brain. The cortex or gray matter is the region of
highest activity; it consumes twice the oxygen and liberates
one and one-half times the carbon dioxide the white matter
of the brain does. Measured by oxygen consumed and car-
bon dioxide produced, the dynamic activity of the cerebrum
is greater than that of the cerebellum. And so on, down
through the various regions of the brain to spinal cord, which
has the lowest rate of all.
Material exchange in one-celled organisms is effected
through the exterior surface. This naturally limits the size of
the organism, both for growth or material relations to en-
vironment and for change or dynamic relations. Hence the
energy requirement of living organisms varies according to
surface area rather than to volume of body. A dog trans-
forms more energy relatively than an elephant; a baby needs
more energy relatively than its father.
Why "naturally"? Because, as we have already seen, any
increase in size causes volume to increase faster than surface.
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THE MECHANISM OF ADJUSTMENT
The combined surface area of one billion amebae is six hun-
dred thousand times greater than that of one ameba with a
volume equal to that of the billion individuals. Using Hux-
ley's metaphor, our fictitious one-billion-amebae-sized ameba
has increased its population (volume) six hundred thousand
times faster than it has increased its import and export
facilities (surface area).
Life cannot do business under such conditions. In the
course of evolution the processes we call "living" began
to occur in exceedingly small bits of protoplasm ; these small
bits (cells, protozoa, etc.) have remained the physico-chemical
units of all living processes and of all living beings.
The second great step in organic evolution occurred when
these units were impelled by certain natural forces to pool
their interests and thus form larger and larger co-operative
organisms.
Now for the behavior, or dynamic relation, of the organism
as a transformer of energy. A raindrop on my hand may be
as effective a stimulus as a cloudburst to drive me to cover.
But a slight stimulus is effective only over part of an ameba.
The stimulus may be so slight that it "dies out" before it is
transmitted across the ameba's body. There is no special
conducting path in the ameba.
I may shout and shout in my room : no one in the office be-
low hears me, although the man in the next room may be
annoyed and the man in the room beyond excited. My voice,
through a speaking tube or telephone wire, is conducted to
the office below, or halfway round the world.
For stimulus to carry across the body of an ameba, it must
be of a certain intensity. The greater the distance across its
body, the more intense must be the stimulus to traverse that
distance. In other words, without definite paths of conduc-
tion it must be assumed that in low organisms every stimulus
is conducted with a loss or decrement and that stimuli of vary-
ing quantity provoke reactions of varying quantity.
Nerves, then, are primarily conductors, paths along which
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WHY WE BEHAVE LIKE HUMAN BEINGS
impulses are transmitted. They do it at a speed of about
400 feet a second. The nature of the impulse they conduct
is not known. Nerves can be artificially stimulated by
mechanical, thermal, chemical, and electrical means. The
impulse itself must be some form of energy. The conduction
is probably electrical in nature, but presumably not like that
of an electric current.
Nerve fiber in man and highly organized animals conducts
impulses on the all-or-none principle. A fly lands on an
elephant's tail. That landing is not an adequate stimulus;
it does not pass the threshold. But if the fly bites the tail,
the stimulus is adequate; it passes the lowest limit (threshold)
which will bring about a reaction. The impulse, being suf-
ficient to pass the threshold, is delivered as a maximal excita-
tion and without decrement, regardless of the strength or in-
tensity of the stimulus.
We may, then, think of life as having moved from a one-
cell hive into a mansion of countless cells because the outside
world of environment excited life to wider activity. It could
make the move only through specialization in the excitation-
response mechanism. With man, that mechanism reached
such perfection with all-or-none conduction and all-or-none
muscle engines that one pistol shot could fire all civilization,
as one small spark can fire a whole magazine of powder.
8
Reflex action requires no reflection; if it did, we should
have no time to reflect. Yet they are from the same word,
"to bend back." In reflection, we turn the memory pages of
a misspent career or whatever it is we are reflecting about.
In reflexes, life itself knows how to act; we may or may not
be conscious of the act.
I am writing. From time to time my eyelids snap shut;
I am not conscious of it, nor is the blinking due to conscious
eff'ort. My eyes blink as fast as dust or dryness stimulates
284
THE MECHANISM OF ADJUSTMENT
certain nerves to close the lids. The stimulus removed, other
muscles open the lids.
If the stimulus is a cinder, mere winking might not remove
it; the lids may be drawn tighter. Meanwhile I become con-
scious: pain has come as a stimulus. I react now. But my
effort to overcome reflex effort may not suffice: I may have to
use strong finger muscles to overcome the pull of less strong
eyelid muscles.
The eye-blink was a reflex action. It started with excitation
in my eye due to an external stimulus. That excitation was
conducted by a nerve to the central nervous system; from
central by another nerve to eyelid muscles: they contracted.
The structure or mechanism involved — receptor (eye), con-
ductor (nerve), effector (muscle) — is a reflex arc; the action
involved in a reflex act. On the other hand, my behavior in
removing the cinder — perhaps involving a mirror, cotton,
match, or a journey to a physician — was a general reaction
and far from simple.
The arc in the eye-blink functioned as a unit; the reflex
act performed a definite service of biologic value. And work
of arc and result of act both transpire without my knowing
or heeding. Only when the arc fails to work, or when the
act fails to remove the cause of excitation, does consciousness
take charge.
The reflex arc, then, is an instinctive mechanism to trans-
late impulse into action. It is the simplest unit of reaction;
the reflex act the simplest adapted or purposive unit-response
to an external excitation. Arc and act made higher organisms
possible. Through them order and unity are preserved in
highly complex forms. With the appearance of brain and
spinal cord as central adjustor for these many arcs, the evolu-
tion of monkeys and man was well on the way.
Why does the eye blink — at a shadow even? Why does an
invisible speck of dust close the eye? Or a speck of pepper
set the lachrymal glands to secreting? Or a sudden strange
noise touch off the whole body, including rate of heartbeat,
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WHY WE BEHAVE LIKE HUMAN BEINGS
change in composition of the blood, activity in a thousand
glands?
What happens, how the excitation is conducted to the
eflPector muscle of eyelid, lachrymal gland, etc., is generally
fairly clear. How the stimulus excites is still a profound
secret. How does the message get on the wire?
At any rate, it does. And it is also in the nature of the
wires to central that messages marked: "Answer urgent" are
given precedence. Herein is the biologic value of the reflexes.
The newborn babe does not have to think about food, much
less have to learn to close its windpipe when swallowing: it
does not even have to learn to suck — and that is a very com-
plex process.
Reflexes are inherited types of action; they go with the
birthright. Some function before the doctor can say, "It's a
boy!"; some appear only after some hours; some, only after
weeks. The grasping reflex is so well developed at birth that
a normal child can support its body by grasping a broom
handle. In a baby born without a brain this reflex persisted
till its death at the eighteenth day. The babe can close its
eyes from birth. The blink-reflex appears in the third month.
It can shed tears in the fourth month.
Some reflexes are simple, such as the eye-blink; some,
complex — many muscles or glands respond, as in tickling;
some spread — diff'erent parts of or the whole body responds;
some, periodic — the reaction is repeated, trembling, coughing,
hiccoughing, sneezing, swallowing.
WTien we are keyed up our reflexes are quick and intense —
tonic. A "nervous" person jumps at anything. A brainless
frog injected with a strychnine solution is very sensitive to
reflex stimuli: the slamming of a door sets it jumping! Mental
eff'ort to inhibit pain intensifies the agony of human beings
suff'ering cramps caused by strychnine or tetanus poisoning.
It is like trying to go to sleep: the harder we try, the wider
awake we are.
Reflex action may be conditioned and habits of reaction
286
THE MECHANISM OF ADJUSTMENT
developed to work like reflexes; otherwise our newborns would
have a hard row to hoe. If we had to depend on our inherited
reflexes and instinctive types of behavior, we should never
be as clever as the bees and ants nor have as much intelligence
as a capuchin monkey.
Man's inherited reflex action repertoire is just enough to
keep him on the floor. A chick and a colt inherit a better
set than that. Ours are of enormous importance and save
us time, eflfort, energy. But what counts most in human be-
havior is the manner in which they are "conditioned" and
what kind of habits are built upon and around them. They
arose in response to certain organic needs ; too often they are
conditioned in ignorance, superstition, selfishness, or vice;
or in the lap of luxury as sources of amusement and family
pride — equally useless for society.
9
Living protoplasm is excitable; with nerves, it is more
easily excitable; with brains, it need not get excited and so
can find time to go a-fishing. The nature of nerves, then, is
to make us nervous. Therein is the real diff'erence between
man and tree: with nerves, the tree would be the higher life.
The baby is a "bundle of nerves" — and gets on mother's.
And grows along at the usual rate, knowing nothing of nerves.
Then, without a second's warning, comes a day when the
youngster cries out, "Got the toothache!"
That means that the nerve back of that "toothache" is
exposed to the world. That is why it cries out: exposure to
the world is not the way nerves were brought up. Nerves
are not accustomed to exposure, nor adapted to contact with
outdoor environment. They are inside performers: they
carry messages from somewhere within the body to something
within the body. The "somewhere" may be a cell or group
of cells on or anywhere within the body, but normally not in
the nerve itself.
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WHY WE BEHAVE LIKE HUMAN BEINGS
No tooth "aches." When certain cells became enamel,
otliers dentine, and others cementum, and united to build a
tooth, they traded feeling for form and surrendered most of
their excitable heritage to become almost solid ivory. That
is why the nerve inside the tooth gets so sore when the tooth
gives it the air, so to speak.
It is the nature of nerves to be extraordinarily sensitive to
and remarkably efficient conductors of excitation. Hence the
whole mechanism of end-receptors: shock absorbers; they
break the news to the nerves, gently but firmly. It is the
nerves' business to send the news to the proper organ for
response. If the news is startling or in code, it will be carried
to the higher brain center for consideration or decoding.
I go along a dusty pike in my bare feet. I cut my foot on
a bit of glass. It does not hurt much; and if I am on my
way to the swimming hole, I do not mind it. Who told me my
foot was cut, or that it was not a tack I had stepped on? Per-
haps a mile of nerve fibre and millions of nerve cells were
involved in carrying messages before I finished with that
cut.
We have big nerves and little nerves, long ones and short
ones, as we have muscles of varying length and size. The
units are cells: in muscles, bound into sheaves; in nerves,
bound into cables — trunk lines of communication. There
the general resemblance ends. Nerve cells are called neurons
— and when inflamed spell neuritis. But they are true cells;
they have a nucleus in a mass of cytoplasm and grow and
in general behave like ordinary cells. But they are unique
in their astounding capacity to vary: in size and shape,
especially in their outgrowths — "infinitely complicated and
bewilderingly complex," Child calls them. Some are as
complex in architecture as elm trees, and are called dendrons;
also called afferent because they carry messages toward
central.
Other outgrowths of neurons are called axons (axis) ; their
branches are fewer and shorter; they are more slender and
288
THE MECHANISM OF ADJUSTMENT
more uniform than dendrons, and may be three feet or more
in length. For example, connection between the cortex of the
brain and muscle in the calf of the leg may be made by two
neurons: an upper motor neuron which extends to the lower
end of the spinal cord, a lower or peripheral motor neuron
of the sciatic nerve which ends in a muscle of the calf. Axons
are also called efferent: they carry messages from central to
glands, muscles, etc. Generally a neuron has only one axon ;
it may have several dendrons.
A telephone wire can transmit messages either way. Liv-
ing protoplasm was organized on that plan. But with neuron
conduction paths impulses are carried only one way. The
axon appeared first; it is more highly polarized than the den-
dron, grows faster, is more sensitive. The dendron is more
primitive, and perhaps plays a part in the nutrition processes
of the parent neuron and hence is a less efficient conductor
of messages.
Each neuron is a distinct entity and is visibly connected
with no other neuron. The branches of an axon generally
interlace into the branches of a dendron of another neuron.
But between is a gap: the famous synapse (tying-together),
the junction between two neurons.
The synapse is something of a puzzler, but of great im-
portance. If it were perfectly understood we should have a
much clearer idea than we have now of many perplexing
problems in human behavior.
Nerve fibre — and muscle cells — conduct impulses without
decrement, on the all-or-none law. At the synapse the im-
pulse is slowed up or even blocked ; or it may be speeded up.
In any event, something happens. Slight resistance is appar-
ently lessened by repeated excitation — ^hence the ease of
action in habit formations. As though a path were worn
smooth with frequent usage. Why? What is the synapse?
There is no synapse in the nervous system of a jellyfish,
nor true neurons; simply a nerve net, Harvey cut a dough-
nut-shaped ring from the disk of a jellyfish, entrapping a
289
WHY WE BEHAVE LIKE flUMAN BEINGS
nerve impulse. That impulse traveled around that ring for
eleven days; 457 miles! No decrement, no slov/ing up of
impulse. Apparently it might be traveling yet had not the
muscle become fatigued and had not the impulse been inter-
fered with by regenerating tissue. Further, in that nerve net
impulses travel either way.
In higher animals, a synaptic system with highly special-
ized neurons having numerous and intricate endings has re-
placed the nerve net. It is a more efficient system in that
it is more modifiable. It provides "an anatomical mechanism
for correlation and co-ordinations of the most intricate pat-
terns, and for the modification of the directions taken by
nervous impulses arising from transient fluctuations in the
relative permeability of the different junctions" (Herrick).
The synapse, then, is a barrier, presumably a living semi-
pervious membrane through which ions, bearers of impulses^
can pass and in one direction only; the physico-chemical
nature of the ions or conducting substance may be thereby
altered.
Synapses have been compared to the valves in the veins
which prevent the blood from flowing backward, but the com-
parison suggests nothing of the role played by the synapse
as a modifiable tissue making for impressionable and plastic
behavior.
With the arrangement of neurons and their processes as
found in higher animals, the complicated patterns of sense
organs, nerves, correlation centers, and response organs of
reflex and instinctive behavior were passible. With the
plasticity of the synaptic tissue, the kinds of memory and
association which make for intelligent behavior were possible.
When that "tooth" begins to "ache" the nerve that carries
the ache impulse to central is not to be hushed up on a stop-
ache order from central. It is central's business to have a
look at that tooth. As it is the nature of nerves to be nervous,
it is the business of brains to attend to nerves— and to see
290
THE MECHANISM OF ADJUSTMENT
to it that they are not exposed to stimuli for which they are
not adapted.
Any one nerve carries impulses toward or away from a
nerve center, not both ways; it is either alferent or efferent.
And when it is overloaded or stimulated above normal in-
tensity, it carries a message of pain in addition. Therein lies
the biologic function of pain.
10
The world into which we are born is not a world of walls,
pictures, floor, rugs, chairs, bed, or even of bath, mother, and
milk. It is a world of matter and energy, of things hot or
cold, soft or hard, sharp or round, sweet or sour, of various
physical and chemical stimuli, of various kinds of physical
energy, vibrations in the ether and in material media.
The world into which we are born is a small world, but it
is a world of stimuli.
Some made us afraid, some made us angry, some made us
smile. What happened when the nurse declared, "It's the
homeliest brat I ever saw"? Much, if the mother heard it;
to us, just born, nothing. The remark was a stimulus, but
created no sensation in us: it was not an adequate stimulus.
If the nurse had bawled that remark in our ear, we should
have heard it — for we were born with ears attuned to the
human voice. And it would have frightened us, not because
of its sentiment, but because of its noise. A loud noise would
have been a real stimulus: sound-waves of such length as to
disturb our inherited equilibrium. We reacted to such rude
noises. They were adequate stimuli.
The world of our environment keeps beating in upon us as
stimuli: pressures, chemical substances, sound-waves, light-
waves. How we interpret these stimuli, what they mean to us,
these make up our world. To no two human beings can the
world seem the same; nor be the same on any given two
days or moments to the same individual. Under different
291
WHY WE BEHAVE LIKE HUMAN BEINGS
circumstances, the Count of Monte Cristo would have traded
his cave for a gallon of gasoline.
Orion's light-waves have been stimuli for men's eyes for
ages. To one age Orion was just "stars," to another age these
same light-waves are a library of astronomy, physics, and
chemistry. A hickory tree is a dozen different things to a
dozen different men; a dozen years later each man has a
different notion of the tree. Same tree.
A bloodhound picks up a scent and is off like a shot and
tracks his man across fields and through forest. The stimulus
that hound picked up means nothing to man. He may root
his nose all over the lot, but he can never smell the truffles
the hog's nose finds beneath the soil.
This outside world of stimulus, then, is real to us only in
so far as stimuli reach us and as we interpret the stimuli. To
other animals there are other worlds than ours. It must be
so. Two men in an airplane see two worlds: how must the
world they see look to an eagle, a lark, a bat, a butterfly?
The world is so different to some animals that their behavior
can be explained in no terms of known sense of seeing, hear-
ing, smelling, or tasting.
Man's tongue cannot distinguish sodium, ammonium,
lithium, and potassium chlorides — they all taste salt; but the
earthworm can, and reacts differently to each.
Cut an earthworm in two. The tail end squirms as though
in great pain. Not a squirm from the other end; it crawls
away as unconcerned as you please. Knife is one kind of
stimulus to head end, something else to the other end.
A marked male m.oth was set free a mile and a half from
a caged female. The male was on the cage the next morning.
Our smell stimuli come in the form of gas or vapor. Some
animals seem to smell vibrations. Ants especially sense
stimuli far beyond human reach.
The white rat can hear a noise, but not a tone; a tunins
fork is no stimulus to its ear. Sound-waves are stimuli to
such as are tuned in.
292
THE MECHANISM OF ADJUSTMENT
A shadow is an adequate stimulus to a starfish. Cut out its
eyespots, the shadow is still an adequate stimulus. Other
marine forms without eyes respond to shadows. "Sensibility
to difference," Loeb called it. Even the ameba senses changes
in intensity of light. Blinded frogs can distinguish red
from blue light through their skin. Yet Watson found that
rabbits and rats cannot distinguish red from darkness.
Possibly all animals below man are color-blind. When the
bull sees red, he sees heat. Radiant heat and light, after all,
only differ in wave-length; both are ether vibrations. Certain
animals evidently sense certain vibrations in their skin which
are not stimuli to the skin of higher animals. Bees are color-
blind, but they can see ultra-violet light rays invisible to
human eyes.
Space relations come to us as certain light- wave stimuli and
we use our stereoscopic vision to determine these relations.
Yet animals without stereoscopic vision and with practically
immobile eyes give evidence of infallible judgment in esti-
mating distance.
How do they do it? We know our world as it reaches us,
as sensation. We know what our sense organs sense; the
range of vibration that is stimulus for eye and for ear; the
range of chemical change that serves as stimulus to tongue,
etc. We know our environment in so far as it serves as
stimulus. Each kind of animal and plant knows its world in
the same manner. And for each of us the world is what we
sense it. For many there are no rainbows, sunsets, or Orions,
except in picture books.
Think again of the child at birth. To how few things is
it receptive! In almost literal truth, it has no "sense" at
all. And yet a normal newborn has all the sense organs or
receptors of sensations it will ever have. They are the an-
alyzers of stimuli from the world outside the body; the
windows of the mind, Herrick calls them. Each can be pene-
trated by or is receptive to only certain kinds and ranges of
external energies. External ear, refracting media of the
293
WHY WE BEHAVE LIKE HUMAN BEINGS
eye, etc., are merely devices which modify, strengthen, or
concentrate, and so make more effective the action of the
stimulus. Rarely is it the fault of the sense organs them-
selves if "having eyes they see not, having ears they hear
not" ; nor if, with the whole world as stimulus, they never get
beyond the vegetable plane of existence.
11
Nerves conduct impulses. An impulse is a push. What
is it that pushes? Pushes what?
I look up: I see stars. I get a crack over the head: I
see "stars." Same stars? With an eye open I see light. I
close both eyes and press my thumb on one eye: I see light.
Remove both eyes and stimulate either optic nerve with
electricity: I see light. Those who have had an eye removed
on the operating table report "blinding light."
What do we see with, then? Obviously, not with the eyes.
Even mechanical pressure on the optic nerve, when the eyes
are removed, produces a sensation of light. We do not
"see" with that nerve; it merely conducts the stimulus, the
impulse — no matter who or what pushed. It must be that we
see with the brain. We do: we also "hear" with the brain.
And if our optic nerve were attached to our ear, stimulus of
ear would be received by the brain as light.
It follows that the impulse which is carried by the optic
nerve may start outside or on any part of the nerve itself,
but once on the nerve the impulse is carried to the brain and
there registers as light, the intensity depending on the inten-
sity of the impulse or stimulus. We say the light is seen by
the eye because the brain projects the sensation to its point
of origin. Pain in the stump of a leg is often "felt" in a
foot that has been amputated.
There may have been neither stars nor light in sight when
I received the crack on the head ; the sight center in the brain
was stimulated: I saw "stars." The optic nerve never carries
294
THE MECHANISM OF ADJUSTMENT
sound impulses. No matter what the impulse that is put on
it, the brain "sees" the impulse as light.
The eye is the outer end-organ of the optic nerve. The
retina is the receptive part; it is part of the brain itself — the
seeing brain. The eye is the most highly specialized of all
sense organs. It is called a special sense organ because
specialized to receive certain stimuli which, carried to the
brain, arouse a special sense, the sensation of sight.
Table of Ether Wave Vibrations ^
Wave lengin
Number of vibrations
per second
jnecepLor
oensaiion
00 to .1 mm.
(electric waves)
0 to 3,000 billion
None
None
.1 mm. to
.0004 mm.
3,000 billion to
800,000 billion
Skin
Radiant
heat
.0008 mm. to
.0004 mm.
400,000 billion to
800,000 billion
Retina
Light and
color
.0004 mm. to
.000059 mm.
(ultra-violet-rays)
800,000 billion to
5,100,000 billion
None
None
.0000008 mm. to
.00000005 mm.
(X-rays)
400,000,000 billion to
6,000,000,000 billion
None
None
*From Neurology, by C. Judson Herrick, 1922, by permission of the author
and the publishers, W. B. Saunders Company.
The eye itself is the receiving apparatus for certain kinds
of physical energy — ether-waves; but it can receive ether-
waves of certain lengths only. Thus, by reference to the
foregoing table, it will be seen that of all the countless ether-
waves that impinge upon our retina our eyes respond only
295
WHY WE BEHAVE LIKE HUMAN BEINGS
to those with a rate of vibration of from 400,000,000,000,000
to 800,000,000,000,000 per second, one octave of the ten
contained in the solar spectrum. These light-waves travel at
a velocity of 186,000 miles a second and vary from 1/30,000
to 1/60,000 of an inch in length. Within this range the
human eye can distinguish up to 230 pure spectral tints and
up to 600,000 degrees of purity and intensity.
Ether-waves vibrating faster than 800,000,000,000,000
per second are called ultra-violet rays and are beyond human
vision. X-rays are the ether-waves shorter than the ultra-
violet. They are less than a quarter of a millionth of an
inch long and vibrate at a rate from 400,000,000,000,000,-
000 to 6,000,000,000,000,000,000 per second. Their pene-
trating power is also astounding; neither flesh nor bone stops
them, nor thin sheets of zinc, iron, or lead. The existence of
the three octaves of the ultra-violet series and the X-rays
series would have remained unknown to man had they not
been discovered by indirect means in physical laboratories.
Above the octave visible to the human eye are the six
octaves of the infra-red. Of this series the human skin is re-
ceptive to waves of from 3,000,000,000,000 to 400,000,-
000,000,000 as radiant heat; as it is also to the octave which
stimulates the eye as light. Thus, ether-waves of the same
energy may be received by the eye as light, by the skin as
heat. The physical stimulus is identical; and presumably
the nerve impulses from skin and eye to brain are identical.
The discrimination is made in the brain. Optic nerve im-
pulses register light; warm-spot impulses register heat.
Beyond the infra-red octaves of the solar spectrum are the
long, slow electric, or Hertzian, waves; they never stimulate
the eye, only the ear when transformed by a Marconi into
waves in material media. Hertz's discovery made the radio
possible.
So also the human ear has its limitations as receptor for
sound-waves or vibrations in material media. The normal
ear is a special sense organ for vibrations of about ten oc-
296
THE MECHANISM OF ADJUSTMENT
taves, from forty feet to one-half inch in length, and from 30
to 30,000 per second. Within this range about 11,000 dif-
ferent pitches can be discriminated. Exceptional individuals
are sensitive to vibrations as slow as 12, as fast as 50,000,
per second. Vibrations ranging from mere contact up to
1,552 per second are received by the skin and sensed as touch
or pressure. Compared to light-waves, sound-waves travel
at a snail's pace, only 1,100 feet a second.
The anatomy of the internal ear is quite as complicated
as is that of the eye, though not so well understood. But
presumably an essential part of the hearing organ is a tiny
membrane in the inner ear which contains about 20,000
exceedingly minute short fibres of varying length. These, it
is thought, vibrate in response to wave-lengths transmitted
within through the ear drum and the complicated mechanism
of the middle ear.
Just as pressure on the eyes may be transmitted as light, so
disturbance within the auditory apparatus registers on the
auditory nerve as sound. Disturbed blood pressure inside the
ears gives rise to such noises as ringing, roaring, rushing, etc.
Both eyes and ears are specialized as to kind and amount of
stimulus they receive; they have selective excitability and so
lower the threshold of excitability for specific stimuli and
heighten it for all other stimuli. The sound of a ticking
watch can be carried through teeth and bones to the auditory
nerve; but the ear will carry a tick so faint that it will not
reach that nerve through teeth and bone.
Our eyes see more and our ears hear more than a gorilla's
not because ours are better receptors or are excited by diff'er-
ent stimuli, but because our experience diff'ers from the
gorilla's; the difference is in the mind's eye and ear.
We do see with the eyes and hear with the ears ; such is the
nature of these receptors. Only it must be understood that
the eye is a photo-receptor, the ear a sound and position
receptor; our sensations of sight and of sound are dependent
on brain cortex, where they rise to consciousness. In dreams
297
WHY WE BEHAVE LIKE HUMAN BEINGS
we see sights and hear sounds — in the brain cortex only; the
receptors or end- organs of sights and sounds may have re-
ceived no stimuli.
When an end-organ is discovered in man's body adapted
for stimuli such as can be transmitted by a nerve and which
can be produced by "conscious thought" in another's brain,
then — and not until then — will it be time to investigate
thought transference and mental telepathy. "Spirits" may
communicate with "spirits" ; but allowing myself a maximum
of "psychic" power — ^whatever that means — I can conceive
of no voice without mechanism, nor noise without friction.
Science may never see with its eye the hydrogen-ion involved
in nerve conduction, nor know how atoms or ether waves
excite living protoplasm, but it cannot get excited about
something it cannot even conceive. When Sir Oliver Lodge
talks with "spirits," he does it outside a physical laboratory
and as a misguided enthusiast, and not as a physicist. To
talk of or to ghosts is to talk of or to a ghost story. Neither
X-rays nor Hertzian waves transcend any known laws of
physics. Thought-transference and disembodied spirits
transcend all the known laws of physics, nature, and common
sense.
12
Taste and smell organs are the other two of our four special
senses. Eyes and ears are somatic receptors and receive phys-
ical stimuli, ether or mechanical waves. Taste and smell
organs are visceral receptors and are stimulated by chemicals
in solution; hence they are called chemical receptors. Smell
is also a somatic receptor, and as the stimuli for smell come
from outside the body, the organ of smell, together with the
organs for hearing and vision, is also called exteroceptor, to
distinguish from proprioceptors and inter oceptors within the
body.
But bear in mind that "special sense" organs are not pri-
298
THE MECHANISM OF ADJUSTMENT
marily organs of special senses; they are special receptors
to receive certain stimuli from the environment. Through
adequate response to such stimuli we make the adjustments
necessary to maintain life. The adjustments are made only
after the central nervous system has analyzed the stimuli.
Thus, to use Herrick's figure, the odor of ethyl-alcohol may
lead to action in the great somatic effector, the motor mecha-
nism, to get the alcohol ; the odor of that alcohol in the mouth
may lead to swallowing it. The first odor was an exterocep-
tive stimulus and led to a distance or somatic reaction; the
odor in the mouth was an interoceptive stimulus and led to
a visceral reaction. The discriminating mechanism was the
central nervous system.
We have a sense of taste; the organ of taste is the tongue.
Is it? Most of the tongue cannot taste anything. Nor can
any of it taste honey from molasses, black coffee from qui-
nine, clam juice from beef broth, or an apple from an onion.
It can feel fine distinctions; it is a better touch than taste re-
ceptor. Taste buds only receive stimuli: sweet, on the tip
of the tongue; sour, at the sides; salty, at the tip and sides;
bitter, at the root. Only these four qualities: sweet, sour,
salty, bitter. The fine discriminations we make in our mouth
are with the aid of our olfactory organ in the nose and with
our tongue as a tactile organ. Tea and wine "tasters'" are
tea and wine smellers. But there is enormous individual
variation in the distribution of the taste buds; they may also
be found in the soft palate, the epiglottis, even in the larynx.
The bitter receptor is a thousand times more delicate than
the salty — because there are more bitter poisons than salty
ones? Why, then, should the bitter buds be at the root of the
tongue?
Taste buds are receptors for chemical stimuli. The sweet
buds are excited by sugar; also by chloroform, lead acetate,
and other things no more chemically related to sugar than
a rabbit. There is sugar in a rabbit, none in lead acetate.
When the sweet bud is excited, it tastes sweet; the bud seems
299
WHY WE BEHAVE LIKE HUMAN BEINGS
to taste atoms or ions. Even the sugar in the blood may be
tasted by victims of diabetes, as may the bitterness of bile
by the victims of jaundice.
A catfish can taste almost all over its body — it has taste
buds scattered around in its skin. Do things taste sweet,
sour, etc., to a catfish?
We smell with our olfactory receptor, the lining of one of
the seven small cavities in our nose. The stimuli are re-
ceived on microscopic hairs bathed in liquid and must enter
into its solution. Man, it is said, has "lost the sense of smell."
At any rate, our smell sense is miles behind a dog's and
probably not as keen as a shark's. Yet the human nose easily
picks up the scent of an almost inconceivably small amount
of an alcohol derivative which smells like garlic and is called
mercaptan.
How small is "almost inconceivably"? It requires a thim-
bleful of air to fill the cavity of the smell receptor. One
460-billionth of a gram of mercaptan evaporated in a thimble
of air sniffed up our nose smells like garlic. What is the
nature of that stimulus? In that almost inconceivably small
fraction of a gram of vapor there are 200,000,000,000 mole-
cules.
Life smelled before there were noses. The skin of the
humble sea anemone is peppered all over with olfactory re-
ceptors. No doubt the ameba smells and tastes. It must have
chemical receptors. It must distinguish useful from noxious
molecules. It may know how atoms taste and smell. It is
certain that a world of environment acts on both animals and
plants without tongue or nose. Yet they are sensitive: they
respond to stimuli. Human beings deprived of the four
special senses manage to live and to experience sensations;
sensations arise in the cortex of the brain.
Of all our special senses, smell sensation dies out quickest.
The first whiff' is the best — or the worst if it is that kind of an
odor. If it is, and dangerous, move; in a few moments it can
no longer be smelled. The odor may last, the smell sensation
300
THE MECHANISM OF ADJUSTMENT
passes. But not the memory: some of childhood's vividest
memories are mixed up with the smell of dust, burning
brush, etc.
While a certain patch inside our nose and certain buds on
our tongue and in our mouth are specialized for certain
chemical stimuli, our skin and the mucous membrane of our
lips, mouth, and alimentary canal can taste acids, mustard,
and all irritating substances. In other words, certain parts
of our body are sensitive to certain chemical stimuli ; they are
less sensitive than the specialized end-organs for chemical
stimuli. For example, ethyl-alcohol in dilution strong enough
to be smelled must be 24,000 times as strong to be tasted, and
80,000 times as strong before it excites the mucous membrane
of the mouth.
In speaking of certain vestigial structures of our body,
reference was made to Jacobson's organ in the cartilage of
our nose. There is some evidence that this vestige still func-
tions as a common chemical sense organ. It originally served
to smell food after it was taken into the mouth and was con-
nected directly with the mouth. These openings exist in
snakes' mouths and receive the tips of the forked tongue; they
can distinguish odors from tastes of food in the mouth. We
cannot. For that reason "all food tastes alike" when our nose
is stopped up with a cold.
13
Every human individual normal enough to live beyond the
walls of an asylum lives because he has an equipment by
which he can keep on making adjustments to changing condi-
tions. The adjustments we make as individuals are indi-
vidual adjustments, and they will be determined by many
factors. But the adjusting mechanism itself has common
features.
Thus we all are, and at all stages of our life are, sensitive
to change. We sense change by receptors which are stimu-
301
WHY WE BEHAVE LIKE HUMAN BEINGS
lated by change. But we fail to realize the nature of recep-
tors, or understand what we sense, if we think our special
sense organs are all or are the supreme receptors. We think
of glands as regulators, and so they are; of our motor
mechanism as effector, and so it is; and of our nervous sys-
tem as conductor, and so it is; but they are also receptors.
Our entire body is receptive, even as we are responsive.
Kinesthetic sense: a sixth sense, it has been called; or pro-
prioceptor, to distinguish it from the five senses of sight,
hearing, tasting, smelling, and touching — exteroceptors which
receive stimuli from without. By the kinesthetic sense we
receive information from within. Without that information
our motor mechanism would be useless, nor could we ever
learn to talk or walk.
Impulses arise in this mechanism: in muscles, tendons,
joints. All have special sense-organ structure. They respond
to pressure. With every contraction of muscle in talking,
writing, walking, etc., pressure is exerted somewhere, nerve
impulses are released. As these muscles are in opposite sets
— to raise or lower the arm or head, for example — we come
to know where our head, arms, legs, fingers, toes, etc., are
without having to look.
We are not conscious of these countless stimuli, rarely
think of them except in pain or fatigue. Nor is it easy to
define the stimulus which affects them, largely because we
learn to use our motor mechanism very early in life. But
they are among our most important sense organs. Normally
our muscles are in tone, neither fully extended nor fully con-
tracted. Such explicit bodily movements as eating, drinking,
talking, smoking, walking, etc., function as perfect habits,
and, once acquired, with as little effort as though they were
inherent habits. It is this kinesthetic sense which enalDles us
to train the motor mechanism to function so perfectly.
The three semicircular canals in the inner ear are most im-
portant sense organs; by the information diey furnish the
body learns to balance itself. Without them we could not
302
THE MECHANISM OF ADJUSTMENT
orientate our body along the line of gravity. Nor without the
supplementary mechanism to the canals could we keep our
head in equilibrium when the body itself is at rest. Orienta-
tion is quite as important as locomotion.
There is an organic sense. Organs, tissues, etc., in thoracic,
abdominal, and pelvic cavities are on the autonomic line of
nerves, but they are also supplied by sensory (afferent)
nerves which reach the central nervous system direct. Mouth,
stomach, heart, diaphragm, peritoneum, and urogenital or-
gans are especially sensitive. Stimuli from these regions
reach central and initiate movements in the motor mechanism.
Indeed our most intimate and personal reactions are in
response to stimuli originating in unstriped or visceral muscle
tissue.
We have an "appetite," we are "hungry," "thirsty,"
"sleepy," "tired": these are real senses. Where or what the
receptors for these senses are is not yet known. But we can
speak of the viscera themselves as receptors. Thus the
stomach is the "receptor" or organ of hunger when its muscles
set up hunger contractions; the throat is an organ of thirst
when its mucous membrane is dry; etc. Herrick distinguishes
further: organs of nausea; organs of respiratory, circulatory,
and sexual sensations; and organs of sensations of distension
of cavities and of visceral pain.
These organic impulses lead to adjustment reactions: food,
water, sex, voidance of noxious stimuli, etc. They are back
of life. Impulses from these unstriped muscles must rouse
action in the skeletal or striped muscles. And so we are
driven to seek water, food, make love, etc. If the motor
mechanism does not satisfy these organic impulses, they fur-
nish the drive for emotional postures and attitudes.
As many of these organic impulses leading to bodily activ-
ity function rhythmically, we are supplied by our body itself
with a reflex basis for a sense of time.
Our skin itself is a marvelous receptor, but it is organized
for certain ranges and kinds of stimuli. These excite special
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nerve endings rather than special organs. One group is sen-
sitive to touch and mild degrees of temperature. When
stimulated the sensation is felt as though it belonged to the
objects themselves. The other group senses pressure and
pain, and heat above 113 degrees and cold below 68 degrees;
the sensations are felt as on or in the skin and not as proper-
ties of the objects which excited the stimuli.
Stimulus to a heat spot is felt as heat, never as pain. Pain
spots can be excited by chemicals, mustard, acids, by cutting,
pinching, etc., by electric current, by freezing or burning, and
by osmotic action such as salt in an open wound. Whatever
the stimulus, the pain spot registers pain: it hurts!
And there are paradoxes. Why does menthol feel cold
and carbon dioxide feel warm to the skin? Or a warm ob-
ject feel cold when applied to a cold spot? Why do we have
chills when we have fever? We speak of feeling "cold to
the very marrow of our bones," but no temperature receptor
has been located within the body.
A hand plunged into hot water presumed to be cold "feels"
cold. A nurse, told to keep her patient's hand in water as
hot as he could "comfortably" stand it, kept on applying
heat. He could stand it — even up to the point where the skin
came off! A frog shows greater ability to "get used to it."
Put a frog in a pot of cold water and raise the temperature
very slowly; the water can be brought to a boil without the
frog showing the slightest sign of feeling. In both cases the
noxious stimulus was too gradual.
Suggestion may explain why the hand felt hot water as
cold, as it explains the difference in the sensation of a wisp of
cotton and a lock of a girl's hair on one's brow. But sugges-
tion does not explain the painless scalded hand, nor did it
keep the frog's mind at ease while it got cooked. The hand
became adapted; loss of skin was the price. The frog became
adapted; it lost its sensitivity and its life. As we do in pro-
longed fever or in starvation.
"What hurts, teaches," says a Latin proverb. That is why
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THE MECHANISM OF ADJUSTMENT
we have pain spots. That is why when in great pain we have
little room for other feelings. A boy might forget a toothache
at a ball game, but not an earache. Severe pain must have
the right-of-way; it is not easily shunted on to a side track.
This can be shown on a dog whose brain has been put out of
action. Stimulation of a pain spot and a pressure spot in the
same region of its leg excites two different nerves: one draws
the foot up as though it were wounded, the other extends the
foot as in walking. Both are reflex movements. But, obvi-
ously, the leg cannot be drawn up and extended at the same
time. ^^Hiich reflex does the brainless dog make? The one
which answers the danger signal, every time.
We may be warned that "the tooth will hurt only a tiny
bit"; we twinge just the same. We jump in spite of our-
selves when we hear a big gun fired; wink, though we know
the experimenter's hand will not reach our eye.
We have reflexes and reflexes. Those which respond to
danger signals take precedence; they are prepotent. No
matter where it comes from or what the excitation, whether
cinder in the eye, frost on the ear, or gas in the intestine,
pain is a call for help. Unfortunately, for many of our pains
we have no adequate reflex response; we call in the doctor
to become the effector of the reflex arc.
But normally we are free of pain. Only when this or that
receptor transmits a message of greater intensity than the
nerve is accustomed to conduct does the message break out
of its beaten path to encounter a path of greater resistance.
Any part of our body may be a receptor of pain. Even a
new idea may be painful to a brain cortex which is all
made up.
Life is sensitive to vital situations and must respond to
meet such situations. But the excitability of living beings
is not a particular this or that; it is an energy-complex played
upon by countless stimuli. Some provoke one kind of
response, some another; most of them none at all — no
response is needed. The response must be adequate, of a
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WHY WE BEHAVE LIKE HUMAN BEINGS
kind appropriate for carrying on. To classify receptors
according to the nature of the stimulus or the kind of energy
which excites them, does not tell us all the avenues by which
the world as stimulus beats in upon our body.
Because our receptors are specialized they are of enormous
importance. Through them we keep in "touch" with our
environment; we smell "the battle afar off, the thunder of the
captains, and the shouting." Through any one of several
receptors we can become excited by fire before its heat
scorches our body.
Through our special senses we see, hear, smell, taste, and
feel our way through life and learn of each other and of the
world in which we live. They are good enough for practical
purposes, but they fall short of human ambition. Science
sees with telescope, microscope, fluoroscope, spectrum, etc.;
hears with amplifiers: hears a bee change its mind and what
wireless waves through the ether say. Herrick asks us to
think of what the world would be to us if our eyes were like
eagles', our noses as keen as dogs', and our bodies sensitive
to Hertzian waves. X-rays and the like, and to other forms
of energy manifestations as yet unknown to us. As we are,
we are earthbound within the limits set by our physical
sensory equipment; ''nor can our thinking transcend the realm
of sense experience."
14
A fly lands on my finger: it annoys me; I wiggle my
finger: the annoyance flies away. There was a slight lapse
of time between landing of fly and wiggling of finger: the
reaction time, the time required for a stimulus to be answered
by a response. It was about .05 of a second.
Why so much time? What was I doing all this time? /
had nothing to do with it. I was not conscious of the perform-
ance; it happens also in our sleep. Had I been conscious I
might have stopped the finger response to admire the tiny
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THE MECHANISM OF ADJUSTMENT
living airplane that had made a perfect landing. I might
have given the fly leave to study my finger as long as it
pleased, wondering why my finger, of all spots in the world,
stimulated it at that particular instant to respond by landing.
It lands: stimulus. That stimulus, as impulse, is put on
an aff'erent or sensory nerve for transmission to central. The
impulse can lead to no response until put on an efferent or
motor nerve ending in an effector, a response mechanism. In
only one place can impulse be transferred from sensory to
motor nerve: central nervous system — brain and spinal cord.
All the switchboards of all the centrals of all the telephone
systems on earth combined into one would be a simple
exchange compared to our own central exchange. This cen-
tral, with the nerve trunks leading in and out and the rami-
fications of the individual nerves of the trunk lines and the
ramifications of the branches of the billions of individual
neurons — this is our nervous system.
That fraction of a second between excited finger and finger
wiggle is the time it took for the impulse to be transmitted to
central, there switched to another nerve to carry an impulse
back to the finger. Same finger. But the impulse started on
the skin of the finger; it ended in certain muscles of the finger.
Reflex action; there is a reflex arc; but central fills the
breach in that arc. The skin of finger cannot talk to muscles
of finger. Skin can inform central, central can give orders
to muscles. Every message that comes to us from outside
the body is carried to central, every response to such messages
is directed from central.
The .05 of a second for that reflex assumes that the
response was automatic: that it was a true reflex, that my
conscious self had no part in it. Several factors enter into
reflex time. Had the fly been a red-hot coal the time would
have shortened : a vital stimulus gets a more prompt response.
Reflex time is also conditioned by the nature of the stimulus :
we respond more promptly to sound than to light. A third
factor is the number of synapses that must be passed. They
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WHY WE BEHAVE LIKE HUMAN BEINGS
seem to act as switches or relay stations to control the direc-
tion of impulses — at one time open for, at another time
blocking, conduction.
The physical contact of fly on finger skin called out the
reflex. But the sight of the fly or the sound of its wings
could have led to the same reflex. In other words, any one
of several distinct kinds of receptors might be excited by the
fly and lead to the same reflex. The messages are distinct:
one from eye, another from ear, another from skin; the
answer from central may be the same.
I was stretched out on a blanket under a tree in Colombia,
sound asleep — noonday siesta. I suddenly found myself on
my feet — and a long green snake in front of me. I was
unaware of awakening or of getting to my feet, or of having
seen the snake until that instant.
What had been the stimulus? My companion, dozing on
his blanket a dozen feet away, had turned over just as the
snake was crawling across my chest. He yelled, "Snake!"
I jumped to my feet. My whole body could perform a reflex
action before my conscious self could take charge of the
situation and make human response: kill the snake. A
cultural reaction. Had my interest been ophidia and not
ethnology, my behavior would have been diff'erent. Brought
up as a Hindu and without influence of Serpent-Eve tradition,
that snake would be alive to-day, for all of me.
Something happens to messages from the outside world
when delivered to central. The word snake might have led
to the same impulsive reflex — an avoiding response; but the
messages already handled by central determined my reaction
to that particular message. We come to have reaction pat-
terns, complexes of behavior. We condition our reflexes;
we condition ourselves. Our nervous system itself becomes
conditioned, is conditioned, day by day, from birth. The
conditioning factors are environment — an East Side tenement
or the Babbitts of Main Street.
In other words, what behaves is not brain nor central
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THE MECHANISM OF ADJUSTMENT
nervous system nor reflex arc, but this boy, that girl, this
woman, that man, integrated by an integrating organ, adjust-
ing through an adjusting mechanism. Behavior, like life,
resides in individual packages. The response of a crowd
may be more intense; even as one wolf hesitates to tackle a
lion, but as one of a pack takes a chance. Crowd and pack
behavior occur because man and wolf vary their response
with the nature and intensity of the stimulus.
The business of the central nervous system is to regulate
and adjust behavior according to the nature of the stimulus.
Few, if any, tissues, structures, organs, glands, muscles, or
vessels of the body are beyond its reach. Our vegetative
processes normally go on without conscious thought, nor can
we control them by our "will." But let one of these processes
go on a strike, central knows. Knows because, as all roads
led to Rome, all nerves end in central. All nerves deliver
their messages to central. Central is responsible for the
behavior of the individual.
Certain nerves end here, others there. There are centers
for this, centers for that. But central functions as a unit; it
functions for a unit — the individual. Nerves so knit together
all parts of the body that central can organize the body as a
whole for life — and finds ways out of difficulties that baffle
man.
A child is born deaf, dumb, and blind. What kind of
mental life is within its reach? That was Helen Keller's
fate. Yet her mental development was astounding and little
less than miraculous.
15
A snowball aimed at me hits a dog. The dog jumps, yelps,
and runs. The next ball hits me. Can you predict my
behavior, as I do the dog's? I cannot. I might jump, yelp,
and run; I might make no outward response. Ten years
later I might marry the girl who threw the ball ; or forty years
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WHY WE BEHAVE LIKE HUMAN BEINGS
later read with dry eye that the boy who threw it had killed
himself with wood alcohol.
The message from snowball was delivered to the spinal
cord. The cord could answer it by making certain bodily
adjustments. Meanwhile the medulla had been informed and
was ready to contribute to the reaction ; by a wink or a sneeze
or a cough, or orders to heart or blood vessels to prepare for
action.
What action? What next? Here is where the 10,-
000,000,000 neurons of the cerebral cortex get into the
picture.
Spinal cord and brain stem (chiefly medulla) are the two
lower divisions of the central nervous system. Cerebellum
and cerebrum are the two higher. The cerebrum itself is the
supreme central; larger in man in proportion to weight of
body or of spinal cord than in any other animal; it is evolu-
tion's latest improvement as central of a central nervous
system.
The eighteen inches of spinal cord is central for a few
important automatic reflexes and receives the thirty-one pairs
of spinal nerves which supply skin, motor mechanism, and
parts of the viscera. It ends in and is intimately connected
with the brain, which consists of the other tliree divisions of
central: brain stem; cerebellum (little brain); cerebrum
(brain).
The medulla of the brain stem, an enlargement of the
spinal cord just inside the skull, is probably the busiest center
of central. Here end all but four of the twelve cranial
nerves; through here almost all impulses pass from one
division of central to another. Every mark I make with my
pencil has first traversed the medulla. It is also a real central
of its own, the center for such important reflexes as winking
(in part), sneezing, coughing, chewing, sucking, swallowing,
vomiting, and the secretion of saliva and gastric juice. It is
also the center for breathing, for regulating the size of the
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THE MECHANISM OF ADJUSTMENT
blood vessels, and for speeding up and slowing down heart-
beat.
The medulla is only one-twentieth of the weight of the
entire brain — and hollow at that! How does it control so
many vital functions? By receiving impulses and setting this
or that mechanism at work. I step into a tub of cold water.
The cold receptors of the foot transmit the news to a center
in the medulla, the medulla orders the blood vessels of the
skin to close in: there is an enemy to proper body temperature
about.
And so it works. On behalf of the medulla? No; on
behalf of the body. The body is always adjusting itself: to
bad air, to poor food, to cold water, to thirst, to fleas and
flies, to summer and winter, to tight shoes and high collars
and corsets, and countless other frills and fads listed in
civilization's catalogue.
The catalogue is prepared in the higher centers of central.
We can live with a bullet hole in the "higher centers"; a
bird-shot in the medulla stops the heart.
While sitting in a chair or walking about the little brain
center is in control. The chief function of the cerebellum
is to keep us right side up. This is more important for
fishes and birds than for some men, and more difficult for
men than for any quadrupeds. But all vertebrates have a
well-developed cerebellum. To preserve our balance and
adjust our equilibrium is an enormously involved process.
No wonder the cerebellum is convoluted and covered with
gray matter. Probably 1,000,000,000 neurons take part in
every move we make to keep straight. To the cerebellum
come messages from the pressure receptors in our feet, from
the receptors in all joints, tendons, ligaments, and muscles,
from the sight receptors of our eyes, and especially from the
position and motion receptors of our inner ears. The cere-
bellum correlates and co-ordinates these messages; adjust-
ments are thus made possible. We can walk like a man, or
swim like a fish, or fly like a bird.
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WHY WE BEHAVE LIKE HUMAN BEINGS
A blindfolded person maintains his equilibrium with
difficulty: the cerebellum is denied one important source of
information needed to adjust the body. The blind man
learns to preserve his balance. Every movement of his motor
mechanism registers in the cerebellum ; the motor mechanism
itself, in whole and in detail, is a receptor. The cerebellum
interprets messages from this sensory field.
The claim has recently been made by Japanese neurologists
that the cerebellum also co-ordinates movements of tongue,
lips, and vocal cords, and therefore regulates speech. In
that case it is both balancing and talking brain.
16
Spinal cord; mid-brain; cerebellum; higher, higher,
higher. Further away from the simple life. But as the
spinal cord is the region which contains the mechanism for
effecting many reflex actions, so the whole central nervous
system is the region for the mechanism for effecting all
actions and reactions. The brain differs from the cord only
in the fact that it contains more and longer reflex arcs or
nerve paths and more numerous connections. Centers are
regions where diverse impulses can be co-ordinated and
appropriate adjustments thereby become possible. There
are higher and higher centers. The cerebrum is the highest
or supreme adjuster.
In a well-filled head the cerebrum does most of the filling;
and what the icing is to a cake the gray matter is to the
cerebrum. This gray matter is called cortex because it is
the bark of the cerebrum. The cortex is also found on the
cerebellum and inside the medulla and spinal cord. It is
made up of actual neuron bodies and their synapses — ^hence
its color, gray. White matter contains the fibers or conduct-
ing structure of neurons. Because of the many deep infold-
ings or convolutions of the brain, the gray matter contains
enormous numbers of neurons. Degeneration of that gray
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THE MECHANISM OF ADJUSTMENT
matter, whether from syphilitic "general paralysis of the
insane" or from other causes, ends in death.
We walk through life like men because we are human
beings and our motor mechanism calls for an upright body
balanced on two legs, one of which must be off the ground
half the time we are walking. Meanwhile, to preserve that
gait, all our body weight except that of one leg is delicately
balanced on a ball half the size of a billiard ball. This is
a very clever trick and requires many months to learn, during
which we get many hard falls. Once learned, we do it with-
out effort the rest of our life, provided we keep sober and
receive no injury to our cerebellum.
Injury to the cerebellum need not be fatal but does throw
us off our stride. We stagger about and in general suffer
from lowered muscle co-ordination. But we can get over
this. The stagger need not be permanent, though the injury
to the cerebellum is. Why?
The cerebrum has taken over the function. This is the
clue to cerebrum. It is neither special organ nor performs
special function : it can learn to do' anything. Its capacity
is incalculable. Its switching capacity alone runs into
figures which make German marks look like gold coin and
distances between stars like diameters on a mile track.
It is because of cerebral gray matter's range of behavior
permutations that a Greek professor could devote a lifetime
to the solution of a new diacritical mark on an ancient manu-
script— to discover just before he died that it was a fly speck.
A child born without cerebrum lived four years. It pre-
served the reflexes it was born with : sucking, crying, sneezing,
grasping, etc. It never learned to recognize its mother nor
how to hold a bottle. It never learned any controlled or
voluntary motions. It would lie for hours and hours in
unchanged position. Of nervous or mental growth there was
none, of intelligence less than that of a decerebrate frog.
If the cerebrum must be labeled, call it the organ of asso-
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WHY WE BEHAVE LIKE HUMAN BEINGS
dative memory and the structural foundation of human
culture.
The cortex of the cerebrum is a clearing-house, or, as Child
calls it, "a deliberative assembly to which reports of matters
requiring consideration come in from the various groups or
bureaus and in which they are considered and action taken
through the proper channels." But before they enter this
highest court they must pass one or more of the lower correla-
tion centers.
In other words, with a toothache on my mind the snowball
that hits me is relatively unimportant and gets scant attention
from me, and could be answered by a mere jump reflex. But
under ordinary conditions the stimulus of snowball reaches
the cerebrum. Then I become conscious; this or that region
of the cortex is intensely active; connections are made with
other regions. A conflict goes on; the solution of the conflict
will determine my reaction. Hesitation on my part means
that the problem is not yet resolved. When a decision is
reached, reaction follows. While the matter is being adjusted
a boy knocks my hat off". This also reaches the cortex: the
lower centers cannot make adequate response to such an
insult! Another region of the cortex becomes the scene of
violent activity.
Consciousness at this or that moment, then, is determined
by the field of our cortex at the moment active: impulses have
come in which must be answered and which cannot be
answered except with the aid of the cortex. Only the cortex
has the complete files of all that has gone before. Only the
cortex can hear all the evidence from all the body: eyes,
ears, and the million and one receptors of a body which itself
is receptor and eff'ector and which in consciousness calls upon
the superadjustor cortex to govern its behavior. If a stimulus
is not of enough importance to require cortex adjustment,
it is not strong enough to get into consciousness.
What messages reach the cortex: odor of a bad egg, burst
of thunder, flash of lightning, taste of a quinine pill, feel of
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THE MECHANISM OF ADJUSTMENT
a red-hot poker, sting of an insult, colic, toothache? They
do, but they cannot reach the cortex direct. As Herrick
points out: "No simple sensory impulses ordinarily reach
the cortex, but only nervous impulses arising from the lower
correlation centers." Of all the messages that reach the cor-
tex, those from the eyes are the purest: they have less sub-
cortical matter to deal with first. "It is no accident that the
visual sense plays a dominant role in human cortical
function."
That the lower courts of the body can perform so many
living functions so well is why so little is referred to the
supreme cortex adjustor, and also explains why so many have
nothing to think about: their body does their thinking for
them.
17
Gall, a Viennese surgeon, was the first to suggest that the
cerebrum or brain proper is a group of organs, each perform-
ing a separate function. Out of that suggestion grew
phrenology and nonsense and finally a disregard for the
cerebrum. No one disregards the cerebrum nowadays, except
under penalty of losing control of all that distinguishes man
from his lowest ancestors. The cerebrum is a single organ,
not yet well understood, but known to be the most complex
structure yet thrown up by the 100,000,000 years of evolving
life.
Real individuality in life begins with the cerebrum. The
less cerebrum, the less power to learn. The greater the
cerebrum, the greater the capacity to learn from experience.
Of all the structures man has inherited, he knows least about
the one which made human culture possible; and because he
has used it least, human civilization has become the senseless
thing that it is.
A lion can learn to lie down beside a lamb, but a moth
cannot learn to let a flame alone. The moth has no cerebrum.
The cerebrum is one organ, but is the central for several
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WHY WE BEHAVE LIKE HUMAN BEINGS
centers or areas of motor and sensory function. These areas
are connected by association areas, large regions of the brain
cortex which have no direct connection with the brain stem,
and stimulation of which leads to no known effect. They are
as yet the unknown, the great silent fields; the "deepest mys-
tery" of the brain, Mitchell calls them. They are the neiv
parts of the brain: "probably blanks at birth and upon them
is recorded the story of a lifetime." At any rate, without
them we could learn no new habits, no conditioned reflexes,
nor become intelligent human beings.
The sensory areas for sight, hearing, and smell are def-
initely located on the cerebrum. The taste areas are not well
known. The skin and kinesthetic sense areas are known;
they are at the endings of the afferent paths from skin,
viscera, muscle, and skeleton receptors. A pain area has not
been localized.
The following motor areas have been localized: face, body,
opening of jaws, closing of jaws, mouth, tongue, neck, vocal
cords, nose, eyelid, ear, chest, shoulder, arm, elbow, wrist,
fingers, trunk, hip, leg, knee, ankle, foot, toes.
Which means that injury to a certain small spot on your
brain cortex puts your toes out of commission. Your right
thumb is paralyzed : injury in the cortex of the left cerebrum.
But when a deformed limb wastes away, it means that tlie
lower motor neurons of the peripheral nerves are destroyed.
Look again over the list of motor areas localized. How
many of these structures can you see with your eyes? Those
localized motor areas of the brain cortex are called the pic-
tured movement areas. You wiggle your thumb: do your
eyes see the muscles involved? No more does the brain see
or know anything of muscle. It knows muscle sensation
because it receives impulses from movement in muscles. It
knows thumb movements through the eyes. As Woods Jones
puts it, the cortex comes to have a vast store of knowledge
of concrete movements, not only of thumb, but of every move-
ment the body makes that the eyes can see.
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THE MECHANISM OF ADJUSTMENT
No repeated pictured movements ever become reflexes.
They must be initiated in the cortex of the cerebrum. With
one-half of the brain cortex injured, we cannot walk or per-
form any voluntary or pictured movements with the other
half of the body. With all the motor areas injured, there
is no learned action in the motor mechanism; certain
reflexes only may remain intact.
The baby learns to put its finger on its foot, to put its toe
in its mouth, to walk, to make all purposive pictured move-
ments, through the conditioning of and learning made possi-
ble by the association areas of the brain cortex. The cortex
itself is the receptive area for diff'erent impressions. In the
association areas they are sorted, stored, blended.
Thus, early conduct is pictured in terms of action. The
child really begins to organize its motor mechanism when it
has memories of past movements. It can then begin to form
pictured concepts of possible future movements. A little
later it can estimate its ability to make movements. And
with this ability, we have dawning consciousness and youth-
ful ideals of conduct.
Davenport speaks of his nine-months-old son: "He cannot
talk, dress himself, or attend to his animal needs. He is
word and figure blind, cruel to the cat, appropriates others'
property, and wants everything at the inconvenience of others.
He is a low-grade imbecile without moral ideals." Which
simply means that of altruistic behavior we have none at
birth and gain none in the first nine months.
Insanity is a disorder of conduct. The pictured move-
ment area of the brain has gone out of action. The body
does not track: one part goes one way, another part does not
go at all. Impulses from all the diff'erent parts of the body
no longer have a meeting place where they can be co-ordi-
nated, and as a result of such co-ordination adjust the body
as an individual unit.
The ideals of conduct conditioned in the growing brain
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WHY WE BEHAVE LIKE HUMAN BEINGS
will have much to do with the roads that will be open or
closed to the adult brain.
The blind boy's brain has its pictured movement areas,
only the "pictures" the eye sees must be supplied through
the aid of other sensory organs. But no sense plays such a
role in human affairs as the visual. No impulses are deliv-
ered to the cortex with so little delay or pass so few sentinels
en route as those from the eyes.
But to take localization areas too literally is to overlook
the real functions of the cerebral cortex. They are associa-
tional rather than specific. The cerebrum is a superimposed
center. It takes on habits — localized centers presumably
thereby come into being; but it can form new habits. It is
the dominant center only when the lower centers fail or dis-
agree. But no area of the cortex is the exclusive center of
this or that or of any particular function. The centers of the
so-called sensory and motor areas are merely "nodal points,"
as Herrick calls them, "in an exceedingly complex system
of cells and fibers which must act as a whole in order to
perform any function whatsoever." In any other sense, a
cortical center for the performance of a particular function
is an absurdity.
Herrick distinguishes two prime functions of the cortex.
First, correlations of great complexity and with many diverse
factors; of value because of the capacity for choice between
many possible different reactions to the situation. Next,
retentiveness of past individual impressions in such form as
to permit of being recalled later and incorporated into new
stimulus complexes. This is a high type of organic memory;
it makes for modifiability of behavior. The mechanism of
correlation functions may be innate; the retentiveness or
"memory" function is presumably acquired after birth and
is the supreme factor in the education of human beings.
With the correlation function we are enabled to give expres-
sion to our original nature; with the memory function we
can modify our innate tendencies and take on the trappings
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of the culture which happens to be the fashion in our own
home town.
18
The first raisin I bit into was wrapped around a quinine
pill. About that time I traded a jackknife for a chunk of
chocolate, which I devoured on the spot — and got sick. I
was thereby prejudiced against two people and thereafter
disliked two things. I can recall no detail of the chocolate
or raisin incident; I only know that the sight of chocolate
is disagreeable, the odor of a raisin unpleasant.
I left a dark kitchen in a hurry and nearly split my head
on an outstretched pump handle. The pump was removed.
Twenty years later I returned to that house. Leaving the
dark kitchen that night, I ducked the pump handle and was
conscious of a tingling sensation on my forehead. I had
forgotten the pump: my body had not forgotten the handle.
Even now, I sometimes feel queer when I leave that kitchen
in the dark.
There are two kinds of memories: one is built into the body
reaction-system and generally is beyond recall; the other is
conscious memory and presumably entangled in the meshes
of the neurons of the brain cortex.
I may search all day through these neurons for a mislaid
name. The next morning I hear some one whistling "Annie
Rooney"; the name pops into my head: Rooney! Conscious
effort failed to stimulate the "Rooney" cells: the whistled
tune excited the right spot.
Every neuron has potential connection with every other
neuron of the nervous system. The connection may be incal-
culably indirect; the paths are there.
A look, a smile, a dimple, may excite a thousand sparks to
fire, a thousand million neurons to activity. The total
reaction will be the product of untold individual reactions,
each complex. Every one of these reactions modifies the
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WHY WE BEHAVE LIKE HUMAN BEINGS
reaction-system. It is not that we pile up experiences, but
that experiences themselves both change the nature of the
system and are themselves determined by the nature of the
system.
The first "dimple" we experienced in life may have been
wrapped around a quinine pill or too much chocolate; we
are thereby "conditioned" against dimples.
Pawlow's classic experiments on dogs laid the foundation
for an understanding of the conditioned or psychic reflex.
By an ingenious mechanical device he could determine when
and how much a dog's mouth waters: a reflex action of the
salivary glands. This reflex normally takes place when the
hungry animal sees or smells food.
A dog fed by one certain person only secretes saliva when
this person appears. The sight of the person sets off the
reflex mechanism: there may be no food in sight. Another
dog, fed only when a certain musical note is sounded, even-
tually shows mouth water whenever it hears that particular
note. If the note were one of 1,000 vibrations per second,
a note of 960 or of 1,100 vibrations calls out no response.
Another dog easily learned to distinguish 110 beats per
second from 100 beats per second of a metronome.
A dog is fed exactly two minutes after a bell is sounded.
Its mouth waters just two minutes after the bell sounds; this
is both a conditioned and a delayed reflex. Many persons
can "set" themselves and dispense with an alarm clock. I
invariably anticipate an alarm clock by about three minutes.
The nervous system itself can keep time.
Another dog was always fed with a ringing bell or a
flashing light : no food when both stimuli were present. Now
note. The dog's mouth begins to water when the bell begins
to ring; while the bell is still ringing the light is flashed; the
flow stops: light and bell are no stimulus.
We go through that countless times in our lives. Suddenly
lose our appetite — for innumerable things besides food. A
stimulus which calls forth a voiding or conflicting reaction
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inhibits a previous stimulus. We "lose" our appetite: for
a man who betrays us, a woman who deceives us. A hair
in the soup shuts down many a salivary gland, a worm in the
salad ends many a meal.
Another dog was fed with a painful electric shock at a
particular spot on his leg. He learned to like it. With no
food in sight, his mouth would water with the shock. The
same shock an inch away from the accustomed spot brought
pain but not salivary reflex.
For "dogs" read "human beings"; especially, "children."
Destruction of this or that area of the cerebral cortex
wipes out such conditioned reflexes as are dependent on the
mechanism of the area destroyed. Destruction of all the
cortex washes out all conditioned reflexes.
Conduction paths develop with us. They get well worn
with use, rooted in habit. Paths that conduct pain impulses
to central may finally fail to deliver "pain" messages because
they have grown accustomed to carry such messages to the
salivary glands or to the gonads; the impulse which should
have registered as pain sets up or heightens activity in food —
or sex-hunger mechanism.
A smile may stimulate a miser to tighten his grasp on his
purse; but he must be a rank dyspeptic in whom the sound
of the words: "Let's eat!" provokes no conditioned reflex
of salivary glands.
19
We get more energy per fuel unit from our own internal-
combustion engine than from any engine we can make, but
our body uses up 75 per cent of it and says nothing about
it. That only leaves us with a quarter of the energy we
transform from food for consciousness. But that is enough.
The vitally important functions of life go on as uncon-
cernedly as though Nature had never invented nerves nor
evolved brains.
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WHY WE BEHAVE LIKE HUMAN BEINGS
The heart is the star performer. Remove it from the body,
strip off its nerves: in a nutrient solution it keeps on beating.
Cut a sliver from it : the sliver keeps on beating. The embryo
chick's heart begins to beat before nerves find it. The heart
is muscle, striated as are ordinary muscles, but involuntary,
as are the muscles of the viscera and blood vessels. "Invol-
untary" muscle is automatic: contracts and expands on its
own. Rhythmic movement is inherent in such tissues.
These internal movements — of heart, countless muscles,
miles of arteries, arterioles, veins, venules and capillaries,
and big glands and little glands — all keep plugging away
in the dark. We cannot will them to stop. Nor by conscious
effort can we slow down the heart or open the valves that
control the progress of food through the alimentary canal,
or stimulate the adrenals to give the blood a few molecules
of its magic-working hormone.
"Involuntary": yes, beyond volition. Automatic: no.
Man is no automaton; nor is heartbeat or gland activity or
any process of life "automatic." Living processes are
responses to food and oxygen; matter is transferred, energy
is unleashed. But some living processes have learned their
lesson so well they seem automatic to us, who must puff and
blow before we reach the crest. Even if we decide to give
up and sigh no more, the most we can do is give up conscious-
ness for a moment: the lungs will sigh out our excess carbon
dioxide for us. We may cry: "Give us air!" but life learned
to get air millions of years ago. We may demand our place
in the sun, but life learned to climb to the sun millions of
years before man was dreamed of.
Life is motion. The capacity to move in response to life's
heeds resides in all living things — ^has always resided in life,
is inherent in life. Life must move to keep in touch with the
air and water and food of life. Man and higher animals
have taken over some phases of movement — and are "go-
getters." They go after water and food. By their sensory
nerves they can see water and smell food. By their motor
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THE MECHANISM OF ADJUSTMENT
nerves they tell their skeletal or striped muscles to go get it ;
sometimes called the peripheral nervous system. But non-
striated muscle and other "vegetative" organs know what to
do with air and water and food when brought within reach.
And if the air, water, or food is bad, they speak up: a
growl in the stomach, a flutter at the heart, a pain in the
kidney. When they speak the cortex listens in. We may
not know what spot or organ is speaking, but we know that
something has gone wrong.
We begin to investigate. We find that our heart, seem-
ingly without nerves, is singularly well connected with the
nervous system. In fact, no other single organ in the body
is subject to such nervous control. Wliy not? Its work
varies with endless conditions. It knows how to beat, but
how is it to know when to speed up for a race or slow down
for sleep? Or whether to beat eighty times a minute for a
man, or only seventy times because it is working for a
woman? The heart must have accurate and detailed informa-
tion if it is to give the best it has.
It gets this information from two sets of nerves. One is the
great vagus or pneumogastric, tenth of the twelve trunk-line
nerves ending in the brain. Its messages slow the heart,
inhibit action. The other nerve is on another line, only indi-
rectly connected with central: it is an accelerator, speeds up
heart action. The two together hold the heart steady as a bit
holds a horse: "gee" means fast, "haw" slow.
A man looks me over — scornfully as it were, and says,
"Oh, gee!" The mere look was enough: it was an accelerator,
my heart beats faster. By what nerve did that look or word
reach my heart, speed it up, and slip the leash on fighting
mechanism? A look can do it. One word can transform a
man as pale as a cool cucumber into a red-faced fury and
prepare him to take on his weight in wildcats.
A fighting man or a weeping woman is in a "state of
mind" — an emotional state. Some dogs and people have
their "emotions" under control, some are always emoting.
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WHY WE BEHAVE LIKE HUMAN BEINGS
Emotions are born of biologic necessity: to meet the sudden
demands when we must run or fight for our lives. To run
or to fight for life requires reorganization of the body. No
battleship ever carries out clear-decks-for-action order with
the speed that the order itself prepares the bodily mechanism
of the sailors who hear the order.
Such co-ordinated visceral action takes place, through the
autonomic system. "Autonomic" because in control of activ-
ities that function with so little reference to the higher brain
centers they seem automatic. It is not an independent system
(nothing is, in the body), only an extension of the peripheral,
and is dominated by the motor nerves of the central nervous
system. It is a motor system; it makes for speedier action
in the motor mechanism.
The cortex may be busy with a poem under a tree. The
sight of a bull puts cortex out of action and switches on the
autonomic system. As a result, the poet can now break his
own record for the hundred-yard dash; or he can climb the
tree. The cortex is still there — if he can use it. Prepared
to run and running are different things. Whether he runs
or climbs, or decides to wait for the bull to make the next
move, will depend, among other things, on how his emotions
have been trained, how his reactions to fear, rage, pain,
hunger, etc., have been conditioned. Even a poet inherits
life's capacity for inhibition as well as for excitation.
The great effector of the body is the skeletal muscular
system. With this the autonomic system is only indirectly
connected. It is more directly connected with muscles which
control the pupil of the eye and change the crystalline lens;
with glands in the mouth, nose, stomach, and pancreas; witli
most of the arteries, the hair-raiser or goose-flesh muscles,
and sweat glands; with the bladder and reproductive organs.
The sixty-odd ganglia or knots of neurons in this system
presumably form subsidiary centers from which orders are
relayed from the central system.
The fact that the autonomic system can be trained is impor-
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THE MECHANISM OF ADJUSTMENT
tant. It means that a reflex mechanism necessary for brutes
can be educated to behave as befits intelligence. The manner
of its education determines whether life is emotion or science.
The autonomic system is sometimes called sympathetic —
not because it has any sympathy, but because the system
connects widely distributed activities. What the system is
called is less important than the realization that nerves carry
impulses into and orders from central, and that nerves and
central function as a unit. The autonomic nerves are simply
part of that organization. It is not nerves that go to school
or are trained; it is the individual.
20
Ever have cramps — in the sea, a half-mile from the shore?
It is bad enough in bed; sometimes sends you out on to the
floor before the cramped muscle unlocks. In the water a
cramp is serious; it may lead to panic. Some one is gen-
erally lost in a panic.
Why does the muscle lock? If I knew I could rewrite the
history of civilization. Whatever cramps are, fatigue is.
Fatigue is as yet one of life's baffling mysteries. Is sleep a
fatigue-killer? We know when we feel rested and when we
are tired. What is tired? Why did it get tired? What do
we feel fatigued with?
Fatigue is a physiological process, as is living, but it plays
such an important part in all learning processes and is such
a responsible factor in human behavior that it must be talked
about even though it cannot be described.
In a cramped leg the muscle is locked, contracted. The
cramp disappears when the muscle unlocks, relaxes. But
contraction is not the normal state of any muscle — ^why does
it lock? Neither is relaxation. Muscles are normally under
some tension — "tonus." This renders them more capable of
response to nerve impulse to contract or relax. But why a
muscle, quite on its own, as it were, goes into a chronic con-
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WHY WE BEHAVE LIKE HUMAN BEINGS
traction, no one knows. Nor is it known why it often
requires more time for relaxation than for contraction.
Muscle works best under certain conditions. That at least
is known. These conditions include hydrogen-ion concentra-
tion, temperature, and load. Under these conditions its
energy yields more work and less heat than under poor con-
ditions. For example, two of us run a mile in six minutes:
poor time, but that lets me in. At the end, you are cool and
fresh and I am dripping with sweat. Most of my energy went
into heat. That is the difference between the labor of a
trained and an untrained performer. But it does not explain
why my muscle engines got overheated.
Nor why, when I begin to tire, my muscles relax more
and more slowly in proportion to the contraction time.
Finally, they do not relax at all, although there has been no
change in the stimulus. This failure is cramp — contracture.
If the cramp occurs in cold water, it is called "cold con-
tracture"; does cold cause the cramp? Otherwise, the cramp
is called "fatigue contracture." Does "fatigue" cause the
swimmer's cramp? Do lactic acid, CO2, and acid phosphate
result from fatigue and cause contracture? Not in my legs.
My toes cramp only when they are tired of being still. That
cannot be "fatigue." The more I use them the less they
fatigue ; nor do they then ever cramp.
Non-striped muscles of viscera may possibly have a
rhythmic beat of their own, independent of any action of the
nervous system. But skeletal muscles perform under impulse
only of nerves. All striped muscles go out of commission
when their nerves are cut. As they do in deep sleep. Ever
pick up a sleeping child? It would fall apart if not held
together by skin and ligaments; complete relaxation of all
muscles of the motor mechanism.
Which shows no "fatigue" if there are sufficient rest inter-
vals between contractions. But after complete fatigue, at
least two hours are required for recovery. All this has been
experimentally proved.
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THE MECHANISM OF ADJUSTMENT
But what is not cleared up is why a repeatedly stimulated
muscle steadily loses its irritability, relaxes more and more
slowly, contracts less and less, and finally refuses to contract,
which fatigues us greatly; or refuses to relax, and that
cramps us.
Is it the nerve ending? Do the nerves which conduct
impulses to muscles, motor -nerves, have their own discharge
rhythm? The nerve joins the muscle fiber at the motor end-
plate. The poison of a plant juice called curare kills that
plate. A nerve impulse cannot pass that plate if there is
curare in the system. But the muscle itself, of course, is not
killed, only removed from nerve impulse, paralyzed. From
which it is assumed that there is some substance at the motor
end-plate which transmits impulse from nerve to muscle.
This substance gets tired or is made tired by a tired muscle.
And whatever fatigue is, or whatever it is that causes fatigue,
this substance when fatigued upsets the all-or-none law of
nerve-impulse conduction: the impulse now passes from nerve
to muscle with a decrement.
It must be so. Muscles are all-or-none performers.
Nerves are all-or-none conductors. A tired muscle is not
receiving the whole impulse, held up by some substance —
which gets fatigued, and makes us all tired.
Here is the point, and a large one: living protoplasm balks
at endless repetition. Life itself is a response to change. It
wakes up at dawn, goes to bed with the sun. Sunrise and
sunset are change. When Johnny's motor mechanism tires
with the lawn-mower, let him take a swimming lesson; that
will rest him. No normal boy suffers fatigue while swim-
ming; although, if the water is too cold, he might suffer a
cramp.
Whether fatigue is CO2 or a function of lactic acid or
hydrogen ions, or whatever the substance it affects, the
presence of fatigue is the sign of enough. It is as though
life said. Give us a change. Even the brainless reflex knee-
kick knows enough to tire of repetition.
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WHY WE BEHAVE LIKE HUMAN BEINGS
21
Knowledge of the human nervous system is miles from
complete or satisfactory. Whatever "mind" is, the mind of
a human depends on nervous control. WTien a nerve is cut,
the mind of the part beyond the cut vanishes ; when the spinal
cord is severed, life itself vanishes, and with it the last trace
of mind — even though excitability remain a few hours longer
in the members.
Living matter is excitable; that is its nature. The nervous
system is the mechanism through which excitation is con-
ducted; its nature is such that excitation is speeded up and
is transmitted over considerable distances. This may involve
the transport of electrons. But whether by this means or by
chemical change, the facts of transmission can be observed
in any biological laboratory.
The nervous system as a whole has come to have what
amounts to a monopoly of the excitable nature and trans-
missible quality of all the other cells of our body.
We may sleep through a hair-cut — so long as the hairs are
cut. Let some be pulled, and we come to. Each hair is
rooted in a nerve; the nerve cries out when excited. If many
are pulled, we change barbers. WTiich means that the
nervous system functions for the entire organism, knits it
into one individual. It is the mechanism of integration.
Through this mechanism individual behavior, individual
response, is made possible.
Our nervous system, then, is more than mere mechanism
of adjustment to environment, more than something which
has excitation and transmission capacity; it is itself the
product of such adjustments as have been made, the up-to-
date product of the original reaction system that began with
life. It has become increasingly complex. That complexity
is the visible expression of that relation to environment on
which all individual existence is founded and which starts
with all individual existence.
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THE MECHANISM OF ADJUSTMENT
Our individual existence starts with an egg which responds
to environmental relations. Our nervous system, at any one
moment of our life, is the conditioned product of the
responses that have been made up to that moment. These
responses have been made on behalf of an individual. This
or that reaction may seem only part response, but all
responses are individual: any particular part response suf-
ficed for the whole organism. The organism of billions of
cells can act as a unit because its nervous system accepts that
office.
The organism is the individual — man. The cells of his
body live their individual lives: they feed and breathe as
individual cells. But they are welded together for a common
purpose — the unified body they serve. The nervous system
permits of individual action in that unified body. It thereby
performs two groups of functions: "the physiological adjust-
ment of the body as a whole to its environment and the
correlation of the activities of its organs among themselves;
the so-called higher functions of the cerebral cortex related to
the conscious life."
As Herrick points out, our own conscious experience has
nothing to work with except the sensory data which is trans-
mitted through the lower brain centers to the cerebral cortex.
Consciousness, then, is action of a kind in the cerebral cortex:
the materials of consciousness are the contents of sense,
sensory data.
We eat and sleep and snore and dream and work and play,
hunt and fish, get rich and get poor, and in short do and think
the usual and unusual things that men do and think. Some-
times we are conscious, sometimes we are not. Consciousness
is an organic mode.
Excitation is movement of ions — charges of electricity. A
tired muscle shows an increase of its normal hydrogen-ion
concentration. Does this account for the failure of the nerve
to conduct excitation in extreme fatigue? A nerve conducts
an excitation; time must elapse before it can again be stimu-
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WHY WE BEHAVE LIKE HUMAN BEINGS
lated: about 1/lOOth of a second. During this interval the
ions are probably restored to their original positions and
other changes that occurred reversed.
There comes a time when we cannot reverse — nor change
our mind; the reaction-system cannot restore our equilibrium;
the motor mechanism cannot be relieved of the waste products
as rapidly as they are formed. Stimuli which disturb the
equilibrium of the physico-chemical reactions necessary for
life cease to be stimuli. Changes in ion concentrations may
disturb the equilibrium but no longer serve as stimuli to
excite changes necessary to meet the next upset. "I will" is
a fine slogan, but the kinetic energy which kicks down doors
and tunnels mountains is never released until the mechanism
is in such position that the potential energy is there. Our
potential energy is force. There must be equilibrium back of
"I will." Back of each heartbeat is a reaction which restores
its equilibrium: it is always dynamic — potential. It can
reverse.
With change to which we cannot reply, to which we can
make no compensation, death comes to heartbeat and to con-
sciousness. The protoplasm coagulates ; death is an irreversi-
ble change.
The egg by which life is transmitted is a clean slate; the
record of change has been erased. At birth the recording
process begins all over again. With adult life most of the
irreversible changes have been made; we have reached
dynamic equilibrium.
Do we do it? Can we explain the nature of our reactions?
Something is known of the nature of water and many of its
reactions have been described, but none explained. Man is
not quite all water. How much of the remainder is hydro-
gen ions, catalyzers, and drugs, is not yet known. Nor is it
quite known what fires our consciousness; the processes of
chemical combustion in living things are not perfectly under-
stood. But it is certain that all brain work involves change
or metabolism in brain tissue. Metabolism in the nervous
330
THE MECHANISM OF ADJUSTMENT
system is yet to be worked out in the biochemist's laboratory.
When it is, we shall know more about memory and conscious-
ness than we do now. But enough is known to give us a
working hypothesis and to rob memory of some of its
mystery.
Neuron metabolism is presumably not essentially unlike
that of other reacting protoplasms, but because neurons are
especially organized for conduction and are highly irritable,
it seems reasonable that they should not only be architec-
turally unlike other cells, but should also be chemically dif-
ferent. They are. In their neurofibrils is presumably the
substance which facilitates conduction of impulses; their
chromophilic substance presumably is the explosive in
excitation.
The chromophilic substance is an iron-containing nucleo-
protein and is found only in the larger neurons and dendrites,
never in the axons. It is presumably not concerned in the
general metabolism of nerve cells; it does presumably con-
tribute to the rapid liberation of much energy during excita-
tion. Herrick finds a rough analogy with fire in gunpowder
and in a lump of coal. The coal burns only at the surface
in oxygen; the gunpowder, once brought to the proper tem-
perature, liberates oxygen internally, so that the combustion
can take place simultaneously throughout the mass.
During intense activity or in extreme fatigue the chromo-
philic substance seems to disappear, to be used up ; when the
neuron is at rest it reappears. In a way, its action suggests
that of an enzyme. For the present it may be regarded as a
catalyzer of neuron energy liberation. It furnishes the kick
back of brainstorms and the explosive in flare-ups; it serves
as a storehouse for the release of energy in long-sustained
mental work.
But a catalyzer is not used up; no more, presumably, is
the chromophilic substance. During rest or inactivity it
reorganizes, as does an enzyme; it is free to enter into a new
complex. Like enzymes, its action is both analytic and
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WHY WE BEHAVE LIKE HUMAN BEINGS
synthetic. It is conceivable that every action of the chromo-
philic substance leads to a structural change in the proto-
plasm of the neuron itself. The neuron, therefore, is not
what it was before. It has learned a lesson; it will react
more easily the next time. There will be less internal resist-
ance, as Herrick puts it. "The change in the 'set' of the
reacting substance makes a repetition of the discharge easier.
It may be transitory or long enduring. This is organic
memory. The same principle may work out in modified form
in the cerebral cortex in connection with conscious memory."
One other point of great importance. Theoretically, if not
actually, every neuron in the body is in contact with every
other neuron in the body; but presumably no one neuron is
in direct contact with any other neuron, at every junction is
a synapse. This junction stops impulses or it lets them by.
It is modified by what it does; it is "impressionable to indi-
vidual experiences." The real importance of this fact will
appear later. The point to be made here is that simple
atmospheric vibrations of certain lengths may strike my ear
drum and be conducted by my auditory nerve as such, but
when these vibrations have been translated by my cortex and
found to mean a word of five letters having an odor like a
polecat, my entire body may suddenly be mobilized for
action. More, I shall be extremely conscious at the time and
a different man for the remainder of my life. And all
because the different protoplasms of my body are knit
together by correlation mechanisms of varying degrees of
complexity, all integrated into one mechanism which adjusts
me and with which I adjust myself.
And as for consciousness. Sometimes I am conscious,
sometimes I am not. During sleep or at rest, the brain is
probably in a state of dynamic equilibrium. Some stimulus
disturbs this equilibrium; where the stimulus ends will
depend on synaptic resistance and neuron thresholds. If the
stimulus reaches the cerebral cortex, I shall probably be
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THE MECHANISM OF ADJUSTMENT
conscious of it — it will then be "conscious activity, the kind
of consciousness depending on the kind of discharge."
When psychology has become quite divorced from psyche
and gets in bed with living beings we shall be able to throw
the word "consciousness" into the discard — along with
"mind" and "memory." Human behavior then will be on a
scientific basis and not a branch of literature or philosophic
or religious speculation. "Mind" will give way to personal-
ity, "consciousness" in general to specfic exhibitions of
learned behavior, and "memory" to the calling out of some
part of the individual's striped or unstriped muscle-tissue
organization.
Do I remember something? Only if I can react it with my
manual, verbal, or visceral mechanism as the case may be.
Am I conscious? Only when the higher brain centers are
stimulated to activity. Have I a mind? Well I am alive —
and must keep on making adjustments until I am dead. And
that adjustment ends my personality and any further be-
havior as a living being.
This conception of a dynamically active cortex is helpful
in understanding several phenomena of general psychologic
interest — sleep, dreams, consciousness, etc. In sound sleep
it is presumably in equilibrium. When we are widest awake,
its equilibrium presumably is quite upset; changes go on
until equilibrium is restored.
But in this connection Watson's warning against over-
emphasis of the role of the nervous system is useful.
Every sensory structure can, when stimulated, excite a
segmental reflex, a reflex involving neighboring segments, or
a reflex involving practically the whole central nervous sys-
tem. Herein lies the neurological basis for the complex
types of instinctive and habitual reflex acts. Central aff'ords
a system of connection between sense organs and glands and
muscles. Interrupt the connection, the organism no longer
acts as whole; some phase of the behavior pattern drops out.
But, in stooping to tie a shoe, for example, or jumping in
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WHY WE BEHAVE LIKE HUMAN BEINGS
fright following a sudden explosion, the tonus of every
muscle, striped and unstriped, in the body, is changed, and
the glands become activated. Action takes place only with
bones, which means more food, strain on the heart, elimina-
tion of waste, etc. While a simple eye-hand co-ordination
brings a well-ordered and integrated response from the whole
organism, such response only takes place with central, but
it can not take place without action in heart, bones, glands,
and muscles.
As to the nature of the processes due to change in equi-
librium, Herrick assumes, for example, that the irradiation
of a nervous discharge into the visual area of the cortex
through the association tracts will be determined by the
existing pathways at the moment open. Which pathways
are open will be determined by previous experience (facili-
tating transmission) and by stimuli of other senses, which
will reinforce, inhibit, or modify the visually excited
nervous discharges, partly by particular patterns of memory
vestiges in the association centers, partly by temporary states
of fatigue, lassitude, interest, etc. — "and it may be by count-
less other factors." But, cortical equilibrium having been
disturbed (by a withering look or a trim ankle), cortical
activity will continue until a new equilibrium is established —
"by motor discharge, by fatigue wilh no practical outcome,
by the fabrication of a new pattern of cortical activity or by
a new enduring 'set' of the reacting system which will modify
all subsequent activity of this system and may appear in con-
sciousness as an idea, a judgment, a decision, a purpose, or
an ideal."
Consciousness is like life: there are criteria, manifesta-
tions, of living things; but, as there is no life in general, so
there is no consciousness in general. There are conscious
modes. The reaction of ameba to vital change is one con-
scious mode, or form of consciousness. Call it instinct,
impulse — what you will; but it is a definite kind or form of
energy transformer. In man, this energy becomes an object
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THE MECHANISM OF ADJUSTMENT
of observation because it influences other centers of energy
transformation. I have the energy to do several things at the
same time — even to be conscious that the robins are greeting
the dawn and that it is time for me to take the air. The fact
of that consciousness is a factor in my behavior and I adjust
myself accordingly. Any other animal with my kind of
adjusting mechanism and with my experience would do the
same.
335
CHAPTER VI
ACQUIRING HUMAN BEHAVIOR
1. A Stork's-eye View of the Baby. 2. Instinctive Behavior. 3. Organizing
the Kinesthetic Sense. 4. The Reflex Basis of Habits. 5. Play and Imitation.
6. The Laws of Habit Formation. 7. Instinctive Emergency Behavior. 8. The
Fear-Hate Organization. 9. Childhood's "Unconscious" Mind. 10. The
Habit of Language. 11. Verbalized Organization. 12. Adjustment by Thought
and by Words. 13. Learning and Remembering. 14. The Changing Situation.
15. Positive and Negative Adaptations. 16. How Habits Are Broken. 17. The
Habit of Sleep. 18. "Prophecy lies in ... 'I have dreamed.' " 19. Learning
to Know. 20. Knowing and Believing. 21. The Individuality of Response.
1
The stork leaves the baby and flies away home. The baby
knows how to live; all it has to do now is to learn to behave.
It can learn many things ; it will be expected to learn certain
things. It is fitted for life; it will be trained to fit into this or
that kind of life. It has an inheritance; it will be asked to
invest this inheritance in the coin of the realm. Its potenti-
alities are unknown; they will now be tested and given rein
to develop or checked by the bit of custom. In short, every
baby is born at a specific time into a specific community witli
definite ways of living and set opinions of those who do not
live that way; to that life the baby is expected to learn to
adjust itself — or, as it is sometimes put, to become an
ornament!
How does it do it?
How does the stork know its way home? We do not know.
We know how to find our way home — and what happens when
we arrive home and cannot find the keyhole, or when we
promise to be home at one and arrive at four. Even a bee
knows its way home- — and makes for it in a "bee line."
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ACQUIRING HUMAN BEHAVIOR
Marked terns carried by Watson in a hooded cage on a
steamer from their nesting grounds off the coast of Florida
to Galveston, returned home in less than a week across the
six-hundred-mile trackless waters of the Gulf of Mexico.
Uncanny? Only because we cannot describe tern behavior
in the familiar terms of human psychology. We only know
that with this homing instinct birds get home; we do not yet
know the nature of the stimulus, whether one or many, or
how this stimulus so excites the bird that it makes its
"uncanny" response. But this we can say: any bird born with
a reaction mechanism that is not responsive to life-or-death
excitations will never grow up to be proud of its offspring.
An eel travels down the Rhine to the sea, and keeps right
on until she reaches the Azores; lays her eggs; dies. Her
progeny return to the Rhine. Salmon are as "uncanny";
from the sea they enter fresh- water rivers and ascend far
inland; deposit their eggs; die. They are in such hurry to
make this journey to the grave that they do not stop on the
way to eat. Young salmon return to the briny deep to grow
up, and find their way back up the very same river to pay
their debt to their kind and to their nature.
During evolution, life has encountered endless situations
and has learned — sometimes only indifferently well — to meet
these situations in endless ways. Some of these ways are
still miles beyond us — as Huxley remarked of his crayfish
after studying it all his life. We see the responses — and too
often interpret them in terms of our own likes and dislikes,
pains and pleasures, work and play.
We think we know why we travel a thousand miles to die in
the old home, and how we find it. But why should a poor fish
of a salmon go hungry for weeks, travel a thousand miles,
breast endless rapids and climb waterfalls, just to polish off
life in the old home? It seems stupid! It is: it has nearly
been the death of salmon. Think of all the salmon ever
canned — all because they insist on going home to die!
We see the responses; we dissect out the reflex arcs of
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WHY WE BEHAVE LIKE HUMAN BEINGS
nervous mechanism and distinguish receptors from effectors:
the behavior still baffles us, because we have only just begun
to try to interpret living beings as dynamically excitable
organisms with a capacity to respond to excitations which to
them have life-or-death value, and which transmit to their
offspring both excitable structure and capacity for response.
We do not know what impels salmon to climb to lakes in
mountains, eels to cross seas, birds to migrate halfway round
the world, amebae to chase their brothers, or men to beat their
wives. We do not even know much about impulses. We do
know that some things, some situations, and some people,
excite us — sometimes more than we are willing to admit or
is good for us. We respond: we may clean up or go broke.
But whatever it is that salmon, stork, or ameba responds
to, we may be certain that the response is an answer to a
question: is it poison or food — shall I eat it or leave it alone?
Friend or foe — and if foe, shall I run or fight? And, in
higher organisms, does she love me or does she not?
These are the three big things in life.
Plants and animals answer these questions, each according
to its kind. One's poison is another's food; one's deadliest
enemy is another's life-saver. Each has its own specific
reaction system — range of capacity to act, range of capacity
to learn. In short, to each species of animals the world is
thus and so; to that world it must respond thus and so; the
individuals of the species are born attuned to the world in
which they must sink or swim.
The baby our stork left is in the same boat. Only, if we
are to understand it, two things must be borne in mind.
Every species of higher organisms, both in plant and ani-
mal world, has its own specific life cycle. A certain cater-
pillar eats and excretes the livelong day to turn into a butter-
fly which lays her eggs while in the cocoon and dies before
she has eaten a meal or flown a foot. A colt dropped to
earth rises up to trot off with its mother. "Infancy" may be
a minute, it may be years. "Adult" life may rise at sunset
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ACQUIRING HUMAN BEHAVIOR
from an imago in the water on the wings of an ephemera, to
mate, drop her eggs, and die before sunrise.
The world into which we are born has little relation to the
world we were evolved to be born into: it is a man-made
world, full of whispers and innuendoes, dark corners and
bright lights, selfishness and greed, stupidity and cruelty, and
many charitable organizations. In course of time these
excrescences will be seen for what they are. Then the years
of infancy can be so spent that the adult can make the most of
his capacity to mend his environment, instead of being so
misspent that he must use all his energy to fit into it or escape
from it.
Eagles have nests, and coyotes holes, but a Iamb has no
place to lay its head except alongside mother, and she must
keep in touch with grass. The lamb begins to jump about
before it is a day old: it may have to run for its life that same
day. Having frolicked fleetness of foot into its legs, it is
prepared for the main business of life — tearing off grass
between gums of upper and teeth of lower jaw.
The baby the stork leaves can neither fight nor run, but
in its innate instinctive nature are biologically useful modes
of response to the two big crises which confront a human
infant. The response to hunger is one. Back of this
response is a mechanism which works like a charm. Sucking
begins when the lips are stimulated, even by an empty rubber
nipple. Food in mouth leads to the next step in this reflex
chain — swallowing. The reflex chain ends with the stimulus
of a full stomach. All this is instinctive behavior. The reflex
is the simplest and most persistent mechanism of instinctive
acts. The two represent a primitive response in a predeter-
mined direction.
Nor does the newborn have to learn to "throw up" a meal
or spit it out, or to lick, hiccough, sneeze, breathe, or make a
face — at quinine, for example. Or draw up its leg when
tickled. These reflex responses are instinctive acts, written
into its inheritance.
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WHY WE BEHAVE LIKE HUMAN BEINGS
In short, we are born with much valuable knowledge picked
up during the millions of years we have been living; but we
are not born with the knowledge where food and water are
to be found, or with a motor which would take us there if
we knew.
Which means that our viscera know how to live ; our motor
mechanism does not know how to carry the viscera to the
things it must have to live on. And we are infants-in-arms
until our motor mechanism learns to perform that service for
us. When that mechanism learns to go after food as well as
the viscera know how to handle food, we are going concerns,
we have some sense. The first sense we acquire is movement
sense, kinesthetic organization.
2
Animals must eat or die; must breed or theii^ kind dies
with them. Their structure and their nature make them
responsive to these two urges at periods also determined by
their nature and by their development. It is also in their
nature that their structure will enable them throughout their
life cycle to make adjustment to vital stimuli.
The higher the animal life, the less set are the inborn
responses, the more flexible the adjustments. A monkey is
interested in more things than is a cat or a dog: it has a more
excitable nature. It learns more rapidly.
The response mechanism and the response repertoire will
be conditioned by the world the animal faces. The lion
learns to jump through a hoop of fire — a situation the lion
at birth did not confront. A monkey learns to pick a lock
or untie a knot. But it is enough for the monkey at birth to
know how to eat and how to hang on to mother: she will pro-
vide the meals and carry the baby along with her. But it is
also necessary that the baby know when it is in pain and have
some means of letting mother know.
With man, "helpless infancy" reaches its maximum dura-
340
ACQUIRING HUMAN BEHAVIOR
tion. Whatever instinct is, man has less need of it than a flea
or even a monkey. A monkey at six knows everything; man
at six has just started to school. But, like the monkey, he is
born with enough to get by the first day.
A wasp leaves its cell fit to fly, sting, and get food. That
is instinctive behavior. It has nothing to do but live ; nothing
to learn but death. The human newborn yawns and looks
about. It does not know what it will have to do. Why
instincts when there are mothers to teach it habits?
The mason wasp (mud dauber) is not so clever with her
stinger as is the saddler with his awl; she does not always
reach the spinal ganglion of the spider she stings; she may
kill it, which then will be no good for wasp's larvae. But if
she does reach that ganglion, the spider is paralyzed and will
live for days. She drags it home, lays an egg on it, and seals
egg and spider in a mud tomb. The egg hatches, the larva
eats the spider, and digs out, leaving the empty shell of the
spider's body within the tomb. The wasp's stinger was ready-
made and her stinging of spider an inherited habit,
instinctive. The saddler has to learn to use his awl. The
awl finally functions like a machine because innumerable
reflex arcs bound like a chain-gang have learned to work
together. The saddler can then use his mind for other things.
Habit is the most important element in human behavior.
Any animal that cannot form a habit must depend on in-
stinct. Instincts make for routine and stereotyped behavior.
The greater the capacity to form new habits, the wider is the
possible range of behavior. This range in man is so great
that stereotyped thought and action are evidence of an ab-
normal mind.
Human culture is back of human habits. Human nature
is back of human instincts. For example, suppose we are
about to enlist or buy life insurance. Are we physically fit?
The doctor puts us in a chair, asks us to cross our legs, and
raps the patellar ligament just below the knee. Our foot flies
out. We smile: we used to play that trick on each other when
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WHY WE BEHAVE LIKE HUMAN BEINGS
we were boys. What can the old knee-kick trick have to do
^sith fitness for military service or life insurance? Or with
instincts?
Much. The rap on the ligament was carried by a sensory
nerve to the spinal cord, from spinal cord by motor nerve to
the quadriceps femoris muscle (in which the knee-cap is em-
bedded) ending in the tibia. This muscle contracted; the
foot kicked out. Spinal cord 0. K. No paresis, locomotor
ataxia, or such.
Every rap on that ligament is followed by a knee jerk.
It is a reflex act and implies a definite reflex arc; such an arc
exists ; we have countless such arcs at birth. It is not learned
or acquired or under control of the will. A ray of light
strikes a newborn's eye : the eye may or may not close, but the
pupil will contract, as will ours under similar stimulus. That
contraction is a reflex act, instinctive: we could not help it.
We often say, "I simply couldn't help myself!" It is the
gospel truth; by no conscious eff'ort are we ever complete
master of ourselves. We may gaze in open-eyed delight at
a blinding flash of lightning and never turn a hair at the most
deafening burst of thunder, but there is a limit of control in
all human flesh; it is the nature of flesh to be sensitive, of
nerves to transmit sensation.
To blink at lightning and jump at thunder and pull at the
nipple and swallow food and relieve the bladder, etc., are all
instinctive activities. Because they are more complex than
mere knee-kick, pupil contraction, and other reflexes, they
are called instincts. Instincts are compound reflexes. If we
could analyze them, we should find an arc for each of the
component reflexes.
Instinctive behavior is unlearned behavior; it functions
with the first adequate stimulus; it is common to man and to
many higher animals; it is complex; it is accompanied by but
not dependent on consciousness; it is explicit or implicit; it
is modifiable.
Go to the ant, sluggard ! is no advice for any human being.
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ACQUIRING HmiAN BEHAVIOR
The ant is a slave to its instincts. It can only react in a
certain way, predetermined at birth, working on an inherited
preformed mechanism. Requiring no experience, it gains
none. The ant is nature's masterpiece of quick and accurate
uniform behavior, as predetermined as an oak tree. Its
nervous system is a ladder; it must climb that ladder. Go to
a monkey, is better advice. No Primate is a slave, unless en-
slaved by man. Ants have been living the same life for
millions of years. A monkey lives more in a year than all
the ants have lived since ants evolved.
Our nervous system is no ladder; it is built around a tube.
It has plenty of reflex arcs, but it is surmounted by a brain
whose big business is to learn and to profit by experience.
The baby's spinal cord is largely organized at birth, but its
big brain is a clean slate. There is nothing known it cannot
learn. With man, plastic behavior reaches its highest point.
We do not inherit instincts, but an instinctive mode of vege-
tative and reproductive reactions; also an instinctive activity
which by the nature of the stimulus says "yes" or "no," a
positive or a negative response. With such activity, we can
learn to walk and pull the cat's tail; we can form habits.
We bump our head against the table; our next response to
table is conditioned. We pull the wrong cat's tail; our habit
of response to cats' tails is conditioned. All our responses
are conditioned. That is the way we learn to behave. We
do not require instincts; we can acquire habits. If we get
set in them, we can forget our brains and live like ants.
Add it up: instincts are inherited habits. Have we more
than a chimpanzee? We cannot say. But we can say that
both of us have enough to start out in life; if not, we are
defective and do not go far. We can also say that our inherit-
ance of reflex arcs exceeds that of the chimpanzee by several
ounces of neurons. As a consequence, we have more nervous
machinery in general, more neurons to load, more paths to
carry the load.
But the fundamental difference between man's and chim-
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WHY WE BEHAVE LIKE HUMAN BEINGS
panzee's inheritance is in parents. Once a chimpanzee, al-
ways a chimpanzee; but a man may become a skunk or a
saint. Think of all the kinds of people you know!
Man's inherited habit-to-live can be modified into thousands
of ways of living. We do not inherit habits of shaving, wear-
ing kimonos, three meals a day, plug hats, skyscrapers, ab-
horrence of pork, four wives, faith in Sunday schools, or
belief in higher education for women. We do inherit parents
who do not want us to disgrace them and who do their best
to bring us up in the way we ought to go.
Which means that human inheritance varies from age to
age and cradle to cradle. Little the newborn cares about a
silver spoon in his mouth — ^he inherited the habit of respond-
ing to an empty stomach; or whether the roof over his head
is copper or thatch — ^he inherited the habit of crawling in
out of the wet.
To describe human adjustments in terms of instincts or
analyze specific human behavior — or our own consciousness
— into instinctive acts, is to stir the mud. Human culture
is the accumulated responses of the man-animal to his man-
made environment. It accumulates, it varies, because man
can and does talk. This seems a handicap at times, but in the
long run it has had enormous consequences. /Without speech
as an organized tool of exchanging, acquiring, and trans-
mitting experiences, human culture is inconceivable.
Life learns. An ameba probably learns new tricks not
inherent in original protoplasm. Man also must learn by
experience. But if you tell me "The water's cold," or "That's
a toadstool," it saves me time. It is this enormous as-
semblage of others' experiences in the form of objects and
descriptions which makes human culture what it is and man's
birthright to-day what it is.
An engineer will build an airplane in less time than it took
him to learn to drive his first nail. But in an entire lifetime
he could not alone assemble the materials for the airplane,
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ACQUIRING HUMAN BEHAVIOR
or, without benefit of accumulated knowledge, learn how to
make one nail.
We inherit no nail-driving habit. We do inherit a motor
mechanism which feels good when functioning. We took our
first lesson in driving a nail when we banged the rattle on the
side of the crib. Later, stimuli of nails, hammer, soft pine,
an environment holding other stimuli to activity; countless
reflex arcs, some already learned in responses to such stimuli ;
thumb smashed, probably! but the nail is finally driven.
And more nails, and more, until finally the carpenter drives
nails from force of habit like an instinct.
3
We learn to skate in summer and to swim in winter, said
James. He meant that our gradually rising curve of learning
reaches a crest — and stops for a while. During summer, we
consolidate all that we learned during winter. With the
next winter, we start from a new level. It is even more true
that we learn both to skate and to swim when we learn to
walk, just as we have made progress in learning Chinese when
we have learned English. But to learn Chinese, or to skate,
or to dance on our toes, we must start early; our muscles
soon get set in their ways.
It is the first walk that is the hardest. The steps we acquire
later in life are mere child's play compared with the first step
the child learns to make. Balancing the body on one foot on
a wire rope is only possible because we learned first to bal-
ance the body on a ball a half -inch in diameter. We speak
of such complex acts as tennis, typewriting, piano playing,
etc. They are complex, but the complex and difficult part
was learned by the time we could walk across the room and
put a finger in the cat's eye.
Do we learn these acts, or are they innate responses that
appear in due time? We know that the newborn's legs are
not only weak, but are not yet shaped for an upright gait,
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WHY WE BEHAVE LIKE HUMAN BEINGS
and that its spine has not yet taken on human curves; legs
and spine grow human. Several years elapse before they are
entirely human in character. But they are human enough to
walk on within twelve or fifteen months.
The response to the first pin-prick is not the simple reflex
of hand going to the spot that is injured. Rather: random,
aimless, uncontrolled, uncoordinated, unadjusted movements
of body, arms, legs. Possibly driving the pin in deeper. Con-
trast these vain random motor-mechanism movements with
the prompt and coordinated pattern-reaction to pain or nox-
ious stimulus; or that of visceral and glandular systems to
pain of pin-prick or to any pain or to any stimulus which the
little mite of protoplasm interprets as deadly.
It may seem much more important that the infant should
know where and how to put its hand on that pin than it is to
get so upset it loses its appetite — and possibly its dinner.
And the madder it gets, the less likely it is to find the pin.
But man was not evolved in a thorn tree, nor were there pins
when the human adjustment system was perfected. Nor has
man yet progressed to the point where he is born adapted to
"all the comforts of a home" and the tenseness of civiliza-
tion. We have to learn to walk and to train our hands and
fingers in such space and to such keys as our fate allots us.
Random and uncoordinated movements represent the range
of our motor mechanism inheritance at birth; except, of
course, the grasping reflex. That comes with us. Many new-
borns can support their body by either hand; by a hand so
tiny and by an arm so frail that it does not appear strong
enough — and does not know enough — to support a half -pint
bottle.
Swimming is not an inheritance. The newborn is afraid of
water, and if introduced to it under painful circumstances
may carry the fear for life.
The earliest body movements are chiefly of an avoiding
nature. A three-days-old infant's nose was lightly pinched.
It began to strike out with its hand. In eighteen seconds tlie
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ACQUIRING HUMAN BEHAVIOR
hand found its mark: it struck the experimenter's hand. On
the second trial it found his hand in two seconds. By the
fourth day the infant's hand had learned its lesson: it could
at once strike the experimenter's hand.
The newborn can turn its eyes toward the light. Not until
days later can it fix its eyes on a light or move them with a
moving light. It will reach out for a lighted candle. But
only after 150 or more trials has it learned to direct its hand
to the flame. A few trials suffice for the infant's hand to
avoid the flame. The more flame the hand discovers, the less
the hand tries to discover. For "flame" substitute "stick
of candy."
These early months lead to simple eye-hand co-ordinations.
But only after long and repeated experiment can the little
hand or finger be directed to the spot which stim^ulates the
eye. So with body and leg movements. Their actions become
definite and sharp only after months of trial and error. Mean-
while the entire motor-machinery grows in size and in strength.
Every movement that comes under control is a movement
learned, useful in the next adjustment movement. Muscles,
tendons, ligaments, become coordinated. Thus habits of
motion and movement are formed. A few years later these
will be put to use in making pies or playing marbles, or
shooting a rifle, or chopping w^ood.
Hundreds of muscles. What can they not learn to do?
But in all this learning countless little habits are formed:
habits because learned. A time comes when the youngster
can pick up a glass of water from the table and carry it to
his mouth; over one hundred muscles involved. Each per-
forms at the right time, does just the needed work and no
more. The levers involved! The wonderful coordination!
No machine works so perfectly as the body machine can.
The great, the essential, the refined, the delicate move-
ments are learned within three years. That little mechanism
grows up with us. Throughout life we call upon it to run, to
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WHY WE BEHAVE LIKE HUMAN BEINGS
swim, to climb, to dance, to jump, to "hold 'em," to "knock
'em stiff."
Movements and motions of the body mechanism can be
learned because muscles, tendons, and joint surfaces are
themselves sources of impulses: receptors, sense organs.
Our brain can thereby organize our body. We walk along
new gravel beds, plowed fields, dusty roads, sandy beaches,
or city pavements, without stumbling or missing a step. We
kick a cat, but not a brick. Nor a hat on April first: we
kicked that hat once — it had a brick under it. We learned.
By experience we learn to walk through plowed fields, through
grass, ashes, leaves. Training, learning, habits of the motor
mechanism.
With this kinesthetic organization we sense hard stone, soft
grass, heavy lead, the resistance of water, bushes, walls. If
we learn to sleep on a feather bed, a hair mattress is as
"hard as a board." The city-bred boy stumbles all over a
farm: his kinesthetic sense has something to learn. Water
looks soft: it feels as hard as rock if we dive in flat. Only
by experience do we learn whether it is safe to jump from
a height upon a pile of leaves or a load of hay. By falling
off a bicycle we learn enough to stay on.
This kinesthetic organization is of enormous importance.
It carries us through life if we have built it up well, giving
us time to choose. The individual who is always stubbing his
toe, spraining his ankle, stumbling over others' feet, running
into doors and sharp corners, falling downstairs, picking up
hot pokers, barking his shins, and "didn't know it was so
far" or "so high" or "so hard" or "so deep" or "so steep" or
"so slippery," has poorly developed kinesthetic sense: he is
inexperienced in movement or without a full complement of
kinesthetic habits.
The motor mechanism starts to school the day the baby
is born. And every mother knows that it is "not still a min-
ute." Within thirty months it has fallen down a thousand
times; walked or backed or bumped into everything avail-
348
ACQUIRING HUMAN BEHAVIOR
able; handled everything greasy, sticky, smooth, rough, hot,
cold, dry, wet, hard and soft, within reach. Falls out of
crib and chair again and again. Finally learns to climb in
and out. Bumps its nose, its head, its shins; gets its fingers
caught in doors. Learns that it can slide down the banisters
and the cellar door and climb up a rope but not a lace curtain.
Very busy months these. There are not enough words to
describe all the motor habits a healthy youngster learns within
thirty months.
The kinesthetic sense only gets into consciousness when
something goes wrong. With our motor mechanism we swim
along, unconscious of the unending and beautifully coordi-
nated movements of bony levers worked by myriads of micro-
scopic muscle engines. Then, without warning, cramps! We
are suddenly conscious of our body machine. Pain anywhere
in muscles, joints, tendons, ligaments, brings our body
machine home to us.
4
Practice makes perfect. Even a car "drives" better after
the first thousand miles. And as for the driver himself! At
the end of the first day he ever drove a car he was a wreck.
For two reasons.
Fear lest he wreck the car: too emotional. He suffered
enough in anticipation to lose a dozen cars, several legs, ribs,
eyes, lives. Other fears under his belt moved him deeply:
was it safe, any possibility of its blowing up, would the gas
hold out, etc.? He did not know his car; it was a great un-
known; the unknown is always a threat. He did not know his
road, nor its manners and its customs, its curves and its
grades. The new way is always a threat : what is around the
corner?
The other reason. His own motor mechanism was tired
all over. Throughout the day his muscles had been tense,
taut as fiddle strings, keyed up for emergency action. His
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WHY WE BEHAVE LIKE HUMAN BEINGS
eyes saw too much, his ears heard too much, and his nose was
on the qui vive for hot boxes, burning rubber, scorched
grease. His control over his car's brakes and gears was
better than over his own. It was as though he were running
his body on high with the emergency brakes on. More than
that: his hands and feet had not learned to coordinate. To
do one thing with one foot and quite a different thing with the
other, steer with one hand and work a brake or gear-shift with
the other, is a learned operation. He had not yet learned it.
He could do it, but at an awful price.
Now he drives three hundred miles a day; is as fresh as a
daisy; has a good time, sees the country, talks his hat off,
smokes a dozen cigars. Does not give his car a thought the
whole day. He is as automatic as his engine.
Same car, same road, same driver. And the same process
in every act of learning, beginning with the act of standing
up or the first walk in life. We have time for the high spots
in life if we have learned how to cross the routine valleys
by force of habit.
Watch a small boy at his first copybook. Face screwed up
in a knot, brow furrowed, mouth open, tongue out, one fist
clutching the desk, the other the pencil, legs tied up tight.
Every muscle in that boy's body is engaged in learning to
write. Finally he learns to write with one arm, and can
smile and wink and let his legs go to sleep. But when we go
to the theater we help kill the villain and embrace the heroine:
we sigh, we groan, we clench our fists.
Do you know which stocking you put on first this morning
or which trousers' leg you filled first? Do you recall how you
felt the first time you ever wore a dress suit, or how long it
took you to put it on, or to learn to tie a bowknot? Can you
bathe, shave, and dress in six minutes? I can do it in less
than five.
A skilled performer at the piano or typewriter or on the
tennis court acts like an automaton. But no mere automaton
— ^human or otherwise — ever makes a great performer.
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ACQUIRING HUMAN BEHAVIOR
For this reason: heightened sensitivity of the central
nervous system increases the response of the reflex arcs. A
tap on flexed patellar tendon elicits no kick when one is
asleep. Sleep means that central has hung up. But try out
the knee-kick with your teeth clenched or your fist tightly
doubled up: more kick. Get real mad: more kick. A lad
of sixteen is given a little instrument squeezed in the hand to
measure muscle strength. He squeezes: so many pounds.
"Best you can do?" "The best." His best girl enters the
room. He now beats his record by several pounds. Central
nervous system more active; everything more active, except
viscera.
A good habit is a well learned habit put to useful purpose.
The competent driver guides his car as a clever boy his
bicycle: the right muscles work to the right amounts at the
proper time and in proper order. A car or a curve or a hole
or a honk ahead is stimulus enough for eye or ear; the ad-
justment is made as though it were a reflex, as easy as pie.
It is an acquired reflex. Paths have been worn for such
highly complex responses as driving an auto, an airplane, a
tennis ball, a pair of chopsticks, knife and fork.
All our habits act by force of habit because these paths are
worn. We awake in the morning and "before we know it"
we are at the breakfast table, or possibly "come to" only
when some headline in the paper catches our eye — perhaps
already half through our breakfast. And yet, before we
"came to," we went through a thousand acts: dressing, shav-
ing, etc., etc., some of them really complex performances
requiring delicate adjustments. And the whole bag of tricks
performed as a result of a single stimulus: a bell, a call, a
ray of sunlight, gastric tetanus, what not. After that one
stimulus one act followed another: as Paine's "Fall of Pom-
peii" followed from one match.
Yet there were a thousand responses available for that
breakfast stimulus. The stimulus was not necessarily fol-
lowed by a yawn, a stretch, push covers down, one leg out,
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WHY WE BEHAVE LIKE HUMAN BEINGS
other leg out, slippers, etc., etc., etc. — one conditioned reflex
touching off another. But that chain of reactions had been
performed so many times that the paths connecting up these
countless reflexes had been worn ; all the other possible paths
of response off'ered more resistance because they had not been
worn by constant action.
A habit, then, is an act so often repeated that it runs itself :
it does not need our conscious attention; we can give our
attention to something else.
The dropped colt picks itself up and walks off": walking
reflex paths all ready for use; he does not have to learn a
thing about walking. Think of the ways a child can learn to
walk, and with only half as many legs as a colt! But whether
the child learns to walk goosestep, Spanish, or in Chinese size-
minus-four, depends on incidence of parents and accident
of locality — for each insists that its own style is right. Nearly
all our early steps are conditioned into habits backed up by:
"Walk like I walk or I'll ..."
The average mortal has only one habit. The one stimulus
which rouses him from sleep carries him through the day
and back to bed and to sleep. All days look alike to him.
Saturday night is also conditioned into the chain: no fresh
stimulus needed for the bath! His body's clock is likewise
set for Sunday. That day, too, goes by according to schedule,
and when done is itself the stimulus to resume a new week.
One habit after another, like a chain, functioning as one.
Works like a clock wound up for life. Makes a perfect
clerk, "hand," or maid.
This one-habit mode of existence is fine; it gives the brain
a complete rest. The possessor need never have a thought!
He is a skilled performer, but never great, on piccolo, at
lathe, behind counter, or on a stool. He does not even make
a good soldier. There must be visceral dynamics — generally
called "guts" — behind a bayonet charge; and high-strung
central — called "brains" — in control for a sharpshooter.
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ACQUIRING HUMAN BEHAVIOR
The difference between action in an automatic machine and in
a human genius is brains.
5
I smile when you tickle me; I cannot help it, it is a reflex.
If you smile back, I will learn to smile when you smile. The
drive in life is hunger. The action in life is to secure food
and mates to satisfy hunger. Play is preliminary action —
trying out, testing the capacity of range of action. It differs
from the reactions of adult life in that it lacks the consum-
mation response or adjustment. The action has no ulterior
motive.
Play is not an instinct; nor is it unique in human beings or
identical in the human race. It is a form of acquired be-
havior. The games I play as child or adult will be con-
ditioned by my bents and especially by social environment.
What is played, who plays it, how it is played, all depend on
learned habits of individual response and can only be inter-
preted in terms of situation, stimulus, and response.
The stimulus back of play — whether of puppies, children,
or adults — is a motor mechanism which was built for action,
glows with action, and in childhood grows best by action.
Weeding the garden or picking potato bugs is action. But
there are drawbacks. Repetition — same stimulus, same re-
sponse ; and no end in sight — there seem to be so many weeds,
so many bugs ; if they are to be cleared out, the pace must be
kept up. That means that the impulse to respond to other
stimuli that may rise and do keep rising up to beckon the
child aside must be repressed.
Play is generally actions of several kinds at the same time.
Even in a game of marbles a half-dozen different activities
may function together. The difference between marbles and
professional baseball is chiefly years: the men have their
game better organized; are better players because more
habituated to it; and stick closer to their game. But some-
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WHY WE BEHAVE LIKE HUMAN BEINGS
times their game becomes lost in a fight with words, catcalls,
and pop bottles.
Margie making mud pies and mother making apple pies
further illustrate the difference between play of children and
of adults and between play and work. Mother's work ends
when the pie leaves the oven. Margie may grow stale over
her pie before she has made one, or she may go right on
making pies until she uses up all the mud. Her impulse is for
action rather than for consummation. She will stop when the
impulse for mud-pie action is replaced by another with more
pull. Such as: "Let's play dolls," or, "Dinner is ready."
Impulse to action; gratification of that impulse; hang the
consequences : of such is the play of children, the daydreams
and castles-in-Spain of adults.
It is of little consequence to Margie if her pie is dough or
too big or too little for her pie pan. And of less consequence
to Johnny when as Heap Big Injun he "scalps" Margie with a
celluloid paper cutter. And if Margie plays the game she
will pretend to be scalped, catch her "blood" in her apron,
and fall down "dead."
What man tied to his job all day does not yearn now and
then to be a Dick Deadeye, a Jesse James, or a Captain Kidd!
Boys can be. They rob, they hold up trains, they capture
ships, they bury and dig up chests of gold. We come from a
long line of freebooters. There is nothing in our inheritance
which savors of factory, treadmill, or office stool. We must
acquire these priceless habits, and often at the loss of our
entire original inheritance, which included freedom to fight
or run, and everlastingly to fool around.
The sheer joy of being alive, the supreme joy of action in
the child! Watch a four-year-old work off his surplus steam.
Not only is every muscle of his body in action, but his face
and his speech box are at work. It is as though his entire
being were so sensitive to excitation that the slightest wind
that blows excites him to new effort.
W^y not? He has only just discovered the most wonderful,
354
ACQUIRING HUMAN BEHAVIOR
the most excitable, the most insatiable mechanism in the
world: a growing human being, himself! That mechanism
discovered, the boy or girl now sets out to discover the world,
and does easier than later in life. Life's innate curiosity has
not yet been crushed; nor has imagination, the capacity to
make believe, yet been killed by the "realities" that grown-
ups cling to like shipwrecked mariners to a rotting spar in
midocean.
Spontaneous. As all life is, outside hoopskirts and boiled
shirts. Impulsive. Where does the impulse come from?
Where does every living impulse come from — ^without or
within? Both. Living beings are expressions of the relation-
ship between conditions that invite life and beings that re-
spond to these conditions. And back of the gratification of
food and mate hunger and the decision to fight or flee is
knowledge, information, trying things out. Testing oneself,
learning one's own capacity.
Play is the beginnings of knowledge. Banging the rattle
on the crib or getting a toe in one's mouth is an early lesson
in wisdom.
Which means that there is no sharp line between playing
Jesse James and being Jesse James. But the child who stops
with a stick for a gun will bring down no bigger game in
later years than he can kill with a daydream. Those of us
who live only in hopes build only castles in our own air.
The practical application is this: two boys will pick more
than twice as many potato bugs as one and pick them faster if
a definite goal is set — a quart, or a quarter. Still better re-
sults can be had by setting a phonograph near by with a good
rhythmic swing to it — say, the "Sambre et Meuse" or the
"Washington Post March." Life hates monotony, but loves
rhythm; in heartbeat, in intestinal contraction, in canoeing,
in poetry, in music.
But do not expect the child to be like you through mere
imitation. The child will smile when smiled at, laugh when
others laugh, yell when others yell, look at what others are
355
WHY WE BEHAVE LIKE HUMAN BEINGS
looking at, listen when others listen, run with or after or from
others, and duck when others duck. One sheep over the fence,
all over. Not a sound at night : one dog barks ; in five minutes
fifty dogs are yelping. We also applaud, hiss, whistle, yawn,
light up, with the crowd. Stimulus and response. Your
lighting up is stimulus for the same reaction on my part.
There is also a more direct conditioned stimulus. I cut
my finger: it bleeds, it hurts; I wince. You cut your finger:
I see blood, I wince. Watch the crowd at a prize-fight. They
duck, they dodge, they "Ouch!" They are only less affected
by the blows than the receivers, or only less jubilant than
the man who delivered them. There is much human nature
on exhibition at the prize ring and swimming hole.
6
Without habits we are in a bad way, as poorly equipped
for life as though we had surrendered to habits — then we are
in a bad way. The clock striking twelve may be adequate
stimulus for me to remove my clothes. If I cannot control
that stimulus, the authorities will: the clock strikes that hour
twice a day.
This is an extreme case, but it will serve. The clock strikes
twelve : bedtime. But noon is not midnight. The mere strike
of twelve is not an adequate stimulus. My bodily mechanism
is not in the habit of running down at the noon hour.
If noon is my hour for food, the stroke of twelve sets off
a different mechanism. If my noon behavior is routine and
well learned, habit will carry me through. I close my book,
adjust my desk, reach for my hat and coat, etc., etc. By
one o'clock I am back at my desk. Habit carried me through
the hour. My conscious activity was planning a vacation.
During that lunch hour I performed hundreds of individual
acts, one after another, in regular order; constituting a fairly
distinct routine or habit of behavior. Although my mind was
busy with fishing tackle, canoes, and such things, / did not
356
ACQUIRING HUMAN BEHAVIOR
have to look out for lamp-posts, breaks in the pavement, or
step-downs at the curb. I had learned to thread crowded
streets, remove my hat on entering a restaurant, eat with a
knife, pay the meal check, etc. All habitual performances:
learned responses, acquired reflexes, habits. Otherwise, the
one hour allotted for my meal would not have sufficed. One
unlearned in city streets might spend a half -hour crossing
Times Square; if unaccustomed to a menu, much time in de-
ciding what to order.
We begin with no acquired habits; we begin at once to
acquire them; with these, to acquire others. But when we
get to be mere bundles of habits, when we knoiv, when our
mind is made up, when nothing can move us, we are through;
we have used up all the blank pages we inherited on which to
write our life.
People do get that way. They lose capacity for new expe-
rience, ability to form new habits, plasticity for new modes
of response to change. "Life is not what it used to be." In
reality, they cannot respond to change. The cab-driver who
cannot learn to drive a car is out of luck. Whole groups
find themselves in midair because they cannot change their
habits fast enough to keep pace with change. Their emotional
reaction is wasted, misspent energy. They do not thereby
change conditions, nor are they themselves thereby adapted.
The champion golfer is not thinking about his stroke: he
knows his golf: it is a habit. He is thinking about the Cup,
or his Girl. If he had to think out each stroke, he could not
even qualify. Ask him to describe any one particular shot
after the game : he probably will not even be able to recall it.
"A centipede was happy 'til
One day a toad in fun
Said, Tray, which leg moves which?'
This raised her doubts to such a pitch
She fell exhausted in the ditch,
Not knowing how to run."
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WHY WE BEHAVE LIKE HUMAN BEINGS
Habit formation — golf, tennis, pitching hay, eating
spaghetti, chewing tobacco, going to church — is at bottom like
any other form of learning. Learning to play the piano or
checkers, to read Greek or talk Choctaw, to solve puzzles or
problems in higher mathematics, involves no new principles
not used in learning to walk or in forming the habit of rush-
ing to the window every time the fire engine snorts by.
Most men shave themselves, but go to the barber shop for
a hair-cut. It was not always thus, nor is it thus in all lands.
Custom. Custom also is habit. Our repertoire of habits is
conditioned by the company we keep. It is not immoral to
eat with a knife, or a vice to drink tea from a saucer; but
men are socially executed for less.
Take shaving. I move from Fiji to Main Street with a
normal face of hair. Decide to shave in sheer self-defense.
Do not like the idea — emotionally wrought up. Two things
follow: I am not likely to forget that shave; if I am not too
excited I will be able to give it the best I have. Law number
one of learning: emotional reinforcement; the reflex arcs are
keyed up for new experience. I may so dislike the idea of
shaving that my emotion takes a real fighting mood; the re-
flex arcs are keyed up to resist.
Not having the shaving habit or habituated to razor-sharp-
ness, I cut myself. More emotion. Never will forget that
shave. Nor am I likely to forget the move which resulted in
a cut. Second law : attention or vividness. Learning to shave
is learning to confine the razor edge to the surface of the
face. Old school of hard knocks. If the cut were serious,
my learning to shave might end with the first lesson. Many
boys stop with one lesson on a pipe.
Cut not serious. And it is finally all off". Shave again next
day. Much easier this time. Suppose I had waited a montli:
less easy; too much time to forget what I had learned well
enough to remember a short time. Memory of first shave
and memory of movements made are difl'erent processes:
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ACQUIRING HUMAN BEHAVIOR
different reflex arcs involved. Third law: recency. No one
learns to play the fiddle with one lesson a week.
The fourth law follows — keep it up: repetition. Practice
makes perfect, wears paths through the nervous system.
I may begin this first shave at the age of forty. I have had
no opportunity in life to form habits of action on a reflected
image, nor have I formed habits of using hands for more
delicate operations than digging yams. I try a half-dozen
times. My face is a sight! I give it up — as many men do;
it is hard to teach an old dog tricks. That is why the boy beats
his father at golf. Law five: every man has his limit. But
with enough stimulus the limit can be extended. If the father
had to beat his son or have his allowance cut off", he would
be more likely to succeed.
7
Every living being has an inborn emergency equipment.
For countless beings the equipment is inadequate; they go
down like flies before new foes, new diseases, new situations.
A large percentage of all the human beings ever born died
before maturity; the emergency may have been a rusty nail,
a venturesome spirit, a backward disposition. Anything
which threatens life or disturbs its peace of mind or upsets the
system is an emergency.
Emergencies cannot be listed ; they are too numerous. Nor
can they be described in general terms ; they are individually
discreet. Half a loaf is always better than no bread, but
there are times when a half -loaf is the dynamic equivalent of
a human life, when half a minute spells victory or defeat, or
life or death. There are few of us whose life at one time or
another has not hung by a thread.
What do we do, what is our response to crisis? Fight or
flee? It depends. The cry of "Women first!" on the Titanic
was enough to keep the men from fighting for the boats: life
was not worth fighting for when the loser was a woman. Nor
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WHY WE BEHAVE LIKE HUMAN BEINGS
worth saving when a spar would only support one: a man let
go of a spar that a woman might live! This is human be-
havior at its highest. Possible because our inborn emergency
equipment can be trained, conditioned, educated, made to
obey the orders of our head. But it is so well organized and
so powerful that few can turn its command over to the cortex,
fewer still who can conquer it. Greater is he who conquereth
self than he who taketh seven cities!
Greater, because self-preservation is the first law of nature ;
and the higher we climb in nature's scale, the better organized
life becomes for self-preservation. Man has more means at
his command for self-preservation than any other animal,
largely because he has more ways of destroying his enemies.
Cities and the "taking of cities" arose in response to man's
desire to anticipate emergencies.
The difference between self-preservation and self-control
is the difference between all gorillas and some men. If man
used only his inborn emergency equipment in a fight with a
gorilla, he would lose — or die of fright before the gorilla
could lay hands on him. Fighting instinct, yes; and fleeing
instinct also. But a worm will turn. A rat will run for its
life; cornered or caught by a leg in a trap, it will fight for
its life.
There is another kind of response, the kind we keep on
making during our unconquered-self lives. We are dress-
ing, already late for dinner. We break a shoestring; we can-
not find a certain shirt stud; and then that crowning insult, we
drop the collar button and it rolls under the bureau. Now
we are mad. We roar like a caged lion; we say words, stamp
the floor, kick a chair, yank out the bureau. Battles have
been lost on account of such trifles.
What happened? Almost everything. Upset — literally.
Lost his head : that is true also. Also lost his appetite. The
wife is so disgusted she loses her temper — and calls him
"brute."
It is a brute reaction. It is a biologic reaction: it requires
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ACQUIRING HUMAN BEHAVIOR
neither learning nor headpiece. Out of our inborn emer-
gency equipment we build up our attitudes, fight windmills
and straw men, and rip and roar up and down the world, or
tremble like a leaf at every breath.
I saw the commander of a United States warship run like
mad four blocks to prevent a black cat crossing his path.
That, to him, meant certain death. Such fears are norms of
behavior; they furnish countless impulses for action. An-
other commander might also have been moved by the fear of
black-cat-calamity, but more moved by his uniform to die in
his tracks rather than run four blocks to head off death.
To be moved though we move not, is no mere figure of
speech. Some movements we can control, if we have learned
control; but not the visceral mechanism which tells motor
mechanism to move, nor adrenin which prepares the whole
body for action.
Even a cat prepares for action. It assumes a fighting pos-
ture, lashes its tail, and spits. Man has no tail to lash and
when he is mad or scared cannot spit because his salivary
glands are out of action; but his internal responses to emotion
are as real as the cat's; the visceral organization retires in
order that the motor mechanism can have all of the body's
energy available. When we are so mad we cannot eat, the
viscera say: "All right, we are not asking you to eat; kill
somebody, or move."
"Every little movement has a meaning of its own," as the
old song declared; it is also true that every movement moves
something. We are never more physiologically correct than
when w^e say, "That moves me." Between birth and death
many are "moved" enough to dig a Panama Canal, yet they
never move themselves up out of the cellar of life.
The difference between being moved to disgust at the sight
of a dead cat and moving to remove the cat is one of life's
little jokes that make human life so interesting.
We are moved with unstriped or visceral muscle. We move
with striped or skeletal muscles. To make a gesture is to
361
WHY WE BEHAVE LIKE HUMAN BEINGS
make an excuse for moving. We are moved with less effort
than we move: our unstriped muscles function without the
cortex. They run themselves, and if we are not in charge they
run us. In mobs and panics they run riot. Every emotion —
anger, love, merriment, jealousy, grief, fear, remorse — is an
implicit bodily movement.
Emotions vary, in individuals, communities, nations, races;
are under different degrees of control; are aroused by vary-
ing situations. Emotions are older than the human race; but
outside the human race are put to no such sublime or ridicu-
lous ends. We do not begin life with specific loves, hates,
and fears. Some can go through life without set hates and
loves. They can look people and things over and decide
whether they are worth loving or hating, and if they are,
possess them or do their best to clear the earth of them. But
as we are, not one in ten can love a Hindu or a Jap or the
other political party. And much of thinking and talking is
in terms of hates and fears and loves. We murder at least
something, if not somebody, every day. And love — there are
quite as many things to be loved as people. In fact, there
'is nothing, it seems, that cannot come within range of our
love, except our enemies. Yet there are those who "hate the
whole . . . sex"; that means half the human race.
Is it in our very nature to hate our enemies, impossible to
love them? Why is the very cornerstone of Christ's teachings
so rarely taken literally? James thinks those "swayed by it
might well seem superhuman beings. Their life would be
morally discrete from the lives of other men, and there is no
saying what the effects might be: they might conceivably trans-
form the world."
They might indeed.
As the world is, hate is given freer rein. Recently it
reigned; and each half of the world besought the same God
to help it kill the other half. We can hate enough to kill, but
killing no longer solves problems, nor hating an enemy con-
vert one.
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ACQUIRING HUMAN BEHAVIOR
Fear is old stufif, out of date. It should be thrown off with
our swaddling clothes. And yet it probably plays a greater
part than hope in the daily lives of most men and women.
Fears are played upon by all sorts of propagandists for politi-
cal, social, and religious purposes. Fear of hell-fire is sup-
posed to lead to love of heaven; fear of "ign'runt foreigners"
to hatred of aliens and so to the closing of the doors. And
the only reason this nation could not be led to hate Germany
as France did was because we could not be made to feel the
fear of Germany as France did.
But for most of us life is only meat and the body raiment.
Same reaction system, same environment: stereotyped be-
havior because our world stands still. And an enormously
valuable emotional reservoir of energy, capable of moving
mountains and giving all life a joy-ride, is expended in hating
those we envy and kicking against the pricks or in fleeing in
terror from our shadows because we cannot shake them off.
And so it is that an instinctive emotional endowment rooted
deep in the body of life and inherent in man and mammals
and all living beings that meet dangerous situations with com-
plex mechanisms which must function as a unit and without
warning, becomes personal and individual. The organiza-
tion of that endowment into specific fears and hates and gen-
eral attitudes favoring negative and positive responses begins
the day we are born.
8
"When I was a child, I spake as a child. I understood as
a child, I thought as a child : but when I became a man, I put
away childish things." Some childish things we do put away,
and we do forget most of the rag dolls, tin soldiers, and mud
pies; but we get our start in childhood for much of our bent
and most of our set. We do not put away our nature. Paul
was an exception.
We are afraid of the dark, of little green worms, of hun-
363
WHY WE BEHAVE LIKE HUMAN BEINGS
dreds of things. And get emotionally excited about them.
Some react to a cabbage worm as they would to a wild ele-
phant or to a mouse; and are as nearly scared to death as
life lets them. It is no merit of their own that they have not
died of fright a thousand times.
We are not born that way. The newborn sets up a fear
reaction only to fearful stimuli: the bang of a door, being
dropped, a sudden push or pull at its blanket; especially by
removing its support. It catches its breath, clutches at any-
thing within reach, closes its eyes, cries, voids waste. Memo-
ries of life in the trees? Why not: sudden noises and move-
ments and withdrawal of support were real dangers then.
The infant could not flee, but it could be scared; later it runs
and hides when it is afraid.
A rat learns to thread a maze for food: it must pass a
trap which always terrifies it. Remove the trap: it jumps
as though the trap were present. A dog chases a cat up a tree
four times a day. Every time the dog appears I appear. By
and by the cat takes to the tree without the dog — my face is
enough to make it climb a tree.
A small dog was tossed into the carriage of a 180-days-old
child. The sudden and unexpected move terrified it. A year
later it showed the same kind of terror at tame white mice.
A door was slammed and at the same time a cat was shown to
a child; thereafter it was afraid of the cat.
The child is afraid of a sudden and loud noise. It hears
the thunder, sees the lightning; it learns to be afraid of the
lightning. If the flash is blinding, it is afraid of the room.
If there is some particular person in the room every time the
lightning flashes, the child learns to be afraid of that person,
lightning or no lightning.
With a what-not loaded with what not in the parlor and a
dresser covered with hand-painted junk in the spare bedroom,
and both parlor and bedroom in perpetual gloom, means must
be found to keep little Willie out. A short-cut is found in
the fact that Willie can be scared. And Willie is scared. By
364
ACQUIRING HUMAN BEHAVIOR
the time he is three, or sooner, he is as big a coward as his
mother was when she was three. He is afraid of the dark;
jumps every time a door is slammed; squeals at the sight of
a mouse; and if a bat flies into the room, the whole house-
hold is in a panic. And everybody has bad dreams. And
little Willie comes out of his nightmare in a cold sweat with
a scream: some ghost story has done its work.
We move about in a lighted room with the aid of our eyes.
In a dark room we are not distracted by what we see and con-
sequently are more alert to what we feel and hear. We keep
meeting with the unexpected, sometimes the sudden — crash of
a falling chair, bark of a dog, bump on the forehead. And
by the time our fear of the dark has become further condi-
tioned by ghosts and hobgoblins, we are more than afraid of
a dark graveyard. And if mother is afraid of strangers and
shows it, we are afraid also, because our habit of expectancy
of her behavior is dislocated.
So with rage. The baby cannot fight, but by cries, slash-
ings with arms and legs, stiffening of body, flushed face,
clenched fists, and held breath, it shows its rage when its
nose is pinched, head held, or its body hampered. And it
soon acquires the ability to kick and slash and scream. I
have seen a boy of two beat his head on the floor in a rage at
being denied something. Such early outbursts are signs of
the coward and the murderer that are in us. The way these
potentialities are trained is the key to character and the clue
to most of our attitudes.
A nurse bathes a child each day, first tickling its feet or
pinching its nose. A habit grows up, functioning like an in-
stinct on reflex arcs. The mere sight of the nurse calls out
a gurgle or a rage. If the nurse wears a blue dress habitually,
the blue dress is enough. If the baby knows only one blue
dress and that blue dress always means tickle or pinch, any
blue dress becomes enough for gurgle or a fit.
We come to hate everything associated with our early hates;
afraid of everything associated with early fears. The ran-
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WHY WE BEHAVE LIKE HUMAN BEINGS
dom fears and rages come to be attached to new objects not
contemplated in the original scheme of kill-or-cure emotional
reinforcement. They become specific. The baby is not
naturally afraid of lightning; it is afraid of a sudden crash.
Nor is it naturally afraid of darkness, snakes, strangers,
graveyards, or black cats.
Our emotions are conditioned in the same nursery in which
our growing body learns its first steps. As the movements of
motor mechanism become habits and so function on smooth-
running reflex arcs, the emotions themselves become organ-
ized: the live-or-die glands and the autonomic nerves learn
special modes of behavior. They take on habits, learn new
responses, acquire new friends, new foes, new fears. The
mouth waters under certain conditions. Fear is called out
under certain conditions. Certain persons, things, situa-
tions, call out tantrums, cries, rages; others are sources of
attachment, loves.
Practice makes perfect — ^hates and fears as well as tennis-
players and card sharps. One does not naturally love a cat
or hate a nurse or fear a mouse. But with practice the thresh-
old is lowered, the message gets a quicker response. Only
intense stimuli at first called out these emotional responses.
But a youngster "nearly scared to death" is already on the
way to be a coward. The child "nearly tormented to death"
has laid the foundation for a vicious temper.
It is like a cork. First time out requires eff'ort. There-
after, any old corkscrew will suffice. By and by, a thumb-
nail.
The function of emotion is quick action and a long memory.
If I am the victim of a $100 counterfeit bill to oblige a
stranger who needs change, I am not likely to oblige the
next stranger requiring change. I might even "take it out
on him." We do such things. The horse-buyer knows that
a horse which has had the mange does not forget it: it is tied
in. He strokes the flank of a prospective purchase. Lip
quivers : that horse had the mange.
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ACQUIRING HUMAN BEHAVIOR
Love, fear, and hate start out together; they grow up to-
gether. Meanwhile, the reflex which enables the newborn to
support its body by its hands soon disappears; the human
mother does not hang her baby on a limb to dry, nor does the
infant have to cling to her while she climbs down a tree. It
disappears from lack of use. The primitive hate and fear
types of behavior would also disappear if they were not at
once set to work.
The adjusting mechanism learns — only too blindly. Until
we ourselves are blind. Having eyes, we see not what there
is but what we think we see. We see with a body that by
nature has a huge capacity to hate that which threatens us,
to fear that which endangers us, to love that which protects
and feeds and tickles us. Our ancestors had to have a fear-
response to the new, the unexpected, the sudden, and the
strange. That is no reason why we should jump, turn pale,
sweat, gasp for breath, close our eyes and open our mouths,
and feel creepy every time we hear thunder or backfire, or
are left alone in the dark, or confront a novel and strange
idea. Nor should the same emotion that makes us fear the
novel and the strange impel us to hate reason — even though
reason interfere with our routine behavior, including atti-
tudes, desires, ideals, ambitions, and loves. We do not get
jealous of reason or want to fight it; but we do get so enraged
at a book that we throw it in the fire, so mad at an opinion that
we would like to crucify the man who expresses it.
The haunting fear in Dickens's day seems to have been
poverty; the supreme dread, the almshouse. What is our
haunting fear, our supreme dread? Have we progressed
very far?
With "pep" we can make decisions, use our heads; but
when the visceral nerves take charge, decisions are made for
us — we are as human as iron filings around a magnet or
famished hogs around a swill barrel. A man in a "towering
rage" is more physically fit for murder than one in cold
blood — that is what a towering rage is for, prepare the body
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WHY WE BEHAVE LIKE HUMAN BEINGS
for action with adrenin. Hate is biologically useful. Do
we save it up for the hateful occasions and get the work out
of it it can do, or squander it right and left?
Fear and rage are twins: born of the same necessity. But
we are born of human parents in a state of civilization. Civi-
lization clings to savagery and brutality because fundamental
emotional states are retained as weapons in the endless battles
of religion, society, and nationality. Biologic fears, hates,
and loves are put to a thousand uses that could never have
been contemplated in the original scheme of evolution. That
scheme says : if your neighbor's eye offend you, pluck it out ;
but that scheme made no provision for theft, swindling, ly-
ing, blackmail, slavery, war. Our scheme does.
Our bottled emotions find curious outlets: giggles, tears,
laughter, shame, remorse, rage, grief, love, fear, as the case
may be ; and take us to fights, dances, games, theater, specula-
tion, futile argument, Monte Carlo, or the Count of Monte
Cristo; or they may end in hysteria, phobias, manias.
The big question for each one of us individually is whether
our acquired repertoire of specific loves, fears, and hates will
suffice to keep us on good terms with ourselves and at peace
with the world. Many a man loses his job because his viscera
have never been educated nor his emotions trained. Note too
that under stress of strong rage or fear activity in the digestive
system closes down, predisposing to intestinal disorders in-
cluding bacterial toxins and consequently to other far-reach-
ing organic changes. Love on the contrary hastens food
digestion and heightens metabolism. Love is a better tonic
than rage or fear.
9
Look at a thirty-months-old boy; better yet, mind him for a
few days! You are looking at Freud's Unconscious Mind,
Watson's Unverbalized Behavior.
Why can we recall nothing of those first thirty months,
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ACQUIRING HUMAN BEHAVIOR
most of us nothing of the first forty months? Enough hap-
pened. If all our bumps, knocks, cuffs, and "repressions"
are locked up in the Unconscious, it is a spacious place.
What became of all the food our blood absorbed during
those months? Some was built into our bodies, some was
used as energy, and what was left over was stored as fat.
What happened to the Don'ts, Naughty-naughtys, and Shame-
on-you's? Some got built in as parts of habits of response.
We learned to love our mother, nurse, anybody or anything
that got conditioned into our response mechanism for loving.
We learned likewise to hate tlie butcher boy who pulled our
ear or pinched us every chance he got; and forever after
disliked everybody who suggested butcher boy. Butcher boys
should be more careful.
Horses also.
A young man is upset by the sight of a horse and will cross
the street to get away from one. This is "strange," we say. It
is a "psychosis," says Freud; and by analysis of the Uncon-
scious can be cured. It is next to nothing, says the psycholo-
gist; all of us have our little peculiarities: some of us are
delighted at the sight of a horse and will cross the street to
pat it or kiss it on the nose. Further, says the psychologist,
I know when I am conscious and that "consciousness" is
simply being conscious; and that I know nothing that I cannot
name or describe. Abnormal behavior toward a horse or
anything else seems mysterious only because we are not in
possession of all the facts or even principal factors back of
the behavior of the individual.
The horse that bit the child made him dislike all horses.
He cannot now recall the bite; his reaction-system can and
does. In one lesson he learned to mistrust a horse. Many
big things are learned early in life with one lesson. Few
pick up a red-hot poker or stick their tongues to an ice-cold bit
of iron twice. One lesson was enough : it took the skin off.
I have no memory of my red-hot-poker lesson, but I have a
scar on my hand; I can recall to memory the skin of my
369
WHY WE BEHAVE LIKE HUMAN BEINGS
tongue I left on the ice-cold iron I was invited to "taste,"
although it left no scar on my tongue. One incident happened
when I was two; the other, when I was six. We have no
memory for our early kinesthetic and emotional organization
— the Freudian Unconscious,
The story of an elephant balking at a bridge where he had
had a mishap seventeen years earlier, although the bridge was
now concrete, may or may not be true. The point is that if
I have an unconscious mind, the elephant has. Also dogs,
goldfish and oysters. Every animal has a dynamic mechanism
that can be shocked at one shock and profit by experience.
Which means: we can all learn and what we learn makes
us what we are — and determines whether we want more of
it or not. Our bodies learn thousands of things we cannot
describe or name. We have a thousand likes and dislikes
for which we can give no explanation beyond: "I just like it,"
or, "I simply can't bear it!"
We remember back to a certain fairly definite period of
our lives ; beyond that our conscious memory is a solid blank,
yet our body acts as though it remembered. It does, but that
is not memory; not by such remembering are we conscious.
If so, there would be no excuse to postulate Unconscious.
It is behavior — no doubt about that. Call it unverbalized.
The unverbalized in us is all that the body learned before
our babblings were organized into speech : modes of response
learned without words. We cannot think about it because
thinking is talking without perceptible movement in speech
mechanism. We cannot be conscious of it — as conscious
is used in psychology, the "act of naming our universe of
objects both inside and out" — because we cannot connect it
up with the mechanism by which we name our universe of
objects. For the same reason, we cannot remember it. Nor
will any amount of psycho-analysis bring it into memory.
Often it can be brought to light with outside help — mothers,
nurses, etc.
Before we take on habits of speech we take on a huge
370
ACQUIRING HUMAN BEHAVIOR
amount of habits of mind: kinesthetic and emotional organi-
zation. Innumerable actions are performed with the skeletal
muscles so often that they function like inherent reflexes.
So also innumerable mental attitudes — prejudices for and
against all manner of people and objects — are called out so
often that the body-mind instinctively reacts. The visceral
muscles and the entire autonomic system "work like a charm."
These early conditioned habits have enormous influence on the
future of the individual.
Watson contrasts the child of four just home from the
movies, who talks you deaf, dumb, and blind, with a child of
twenty-seven months who is a skillful performer on a large
kiddy-car. He could guide it, coast downhill, and make all
the adjustments. His kinesthetic organization was complete
master of the car. But "Billy ride kiddy-car" was his only
parallel word organization. Which means that Billy has no
memory organization of these bodily processes except when
he is so placed that he can exhibit the bodily organization.
Billy had been a bottle baby. At the age of twenty-seven
months he was tested as to his memory for a bottle. At the
regular hour he was told, "Dinner ready," and put in a crib
and handed a bottle, as was the custom fifteen months before.
Billy reacted like a tramp who asks for pie and is given an ax
— ^he got mad. Dinner? In a crib with a bottle of milk?
Crib meant nothing to him. He had never learned to be
afraid of it; he had forgotten it. The crib habit was gone,
buried beneath other habits. Bottle also. "Dinner" to him
was meat and vegetables. When the nurse said, "Take your
milk," Billy began to chew the nipple — thought it was a new
kind of meat! And he looked at his mother with disgust for
cheating him out of his dinner.
The entire crib-bottle-nipple-sucking-smiling habit was
gone. Neither objects, faces, nor words used when Billy was
a bottle baby could now call out any of the old habit re-
sponses. Adults often choke when they try to suck through a
straw : it has been so long since they used that inherent habit.
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WHY WE BEHAVE LIKE HUMAN BEINGS
Infancy is infancy, the next stage after fetal life. Dur-
ing infancy we prepare to shift for ourselves. That is the
biologic significance of infancy. It is no more unnatural or
unconscious than fetal life. We learn, take on, acquire,
habits of behavior.
We may form incestuous attachments: have an (Edipus or
an Electra complex. But such attachments are not talked
about, because, as Watson says, "society is not organized to
ban incestuous attachments in the making"; there were no
repressions. Habits connected with "the slowing or speeding
of the sexual organs" have not been verbally organized. Few
men and fewer women have paralleled their sex organization
with words.
Most of our emotional organization, from infancy to old
age, is never verbalized. There are neither adequate words
nor social mechanism for word conditioning of the infant.
Elimination, eructation, releasing gas, masturbation, etc.,
were verbalized only when exhibited in the presence of others.
In short, nearly all visceral and emotional habits are as a rule
learned without parallel verbal organization. They make up
our unverbalized behavior.
10
An Egyptian king wanted to learn the original language,
possibly the speech of the builders of the Tower of Babel be-
fore their language was confounded. He had some children
brought up by deaf mutes. The children learned the deaf-
mute language. There was no more an original language
than an original bill of fare or an original wardrobe.
The bullfrog's spouse call has probably changed little since
the first frog, impelled by love and with the aid of vocal
cords, lifted up his voice. If there is an "original" language,
we shall find its purest form in a frog pond on a summer
night. In the years of evolution that voice developed in
various directions and was put to various ends, but wherever
372
ACQUIRING HUMAN BEHAVIOR
there is voice there is a sensori-motor mechanism back of it.
This mechanism reaches great perfection among birds and
mammals, especially among Primates.
Can monkeys talk? They do: in articulate speech, by
grimaces, by signs. They talk all they need to; they under'
stand one another. To that extent their language is as definite
as ours. The more one studies the apes, the greater the
puzzle as to why they do not learn to speak English; we do
not yet know that they cannot. But it is conceivable that a
chimpanzee, brought up from birth and conditioned by human
voices, could learn to distinguish and make response to several
hundred words.
Accustomed as we are to regulated flows of conversation,
monkey and other mammal talk seems largely exclamations:
cries of rage, fear, pain, courtship, etc. It is emotional
language. Monkeys especially have a large repertoire of
finely shaded emotional calls. How many and what the
shades and tones signify, we do not know. There are individ-
ual variations; the mother monkey knows when her own
youngster shrieks for help.
That is about the extent of our inherent repertoire. We
can all cry and grunt, and we have our own key and pitch;
with that our voice training begins. A mother easily dis-
tinguishes the cry of her child from among twenty-five babies
in a nursery. These cries presumably diff'er with emotional
states — hunger, pain, rage, fear, etc.
Within thirty days a normal infant's voice begins to roam
around, as its hand and arm do; as though it were trying its
voice out. It has a vocal mechanism; it exercises it. All
living mechanisms are excitable, tongue especially. A cur-
rent of air is always available in breathing; that current
flows between vocal cords and through a resonator. Lips in
certain position, tongue in certain position, cords vibrating:
sounds result.
It is a long road between early random sounds and the
first word, as it is between random reachings out and grasp-
373
WHY WE BEHAVE LIKE HUMAN BEINGS
ing a cup. But a sound is a sound and the ear of the child
hears the sound. The sound means nothing definite to the
child's ear at first. Early sounds are as general and as aim-
less as random squirmings elsewhere in its body mechanism.
Some excitatory stimulus — a pin, a tight bandage, oxygen or
food starvation, thirst, slamming of a door, the glow of a full
stomach, the comfort of a warm bed — is impulse for action.
Its range of reactions is limited and as yet unlearned, untu-
tored by experience. It has not learned definite responses.
It has not yet learned to walk to the tap and draw a cup of
water; it has not yet learned that "Dink!" will bring the
water.
The baby's ear hears the sound; it makes it again, as it
reaches for its toe again once it has discovered how. And
again. And again. In all living matter nothing functions
as fast as babies. M, N, NG, H, W, Y, R, OW, 0, E, long A,
short A: all in thirty days. Hearing others produce these
sounds becomes stimulus for repeating them. Baby is given
a rattle and says, "Oh." Mother says, "Oh, baby." Baby
bangs the rattle and chatters, "Oh, oh, oh," like a magpie.
It has begun to learn English.
But habits of language begin somewhat later than other
activities such as are performed with hands, arms, legs. Be-
fore baby can say "water" or "drink" it has learned appro-
priate responses to hundreds of objects and many complex
situations.
With more vocal building-blocks more sounds are pro-
duced. There comes a day when baby wants something. It
jabbers away. And finally says, "Dada." Great excitement.
Wants its father! He is produced. It was not father that was
wanted. Other articles are produced. A rag doll. That is
what baby wants! "Dada" means rag doll! "Dada" may
be the baby's word for rag doll for months. Every baby
has its own vocabulary. Words become substitutes for bodily
movements. Language habits replace bodily habits. Before
the baby can understand the language of its parents, the
374
ACQUIRING HUMAN BEHAVIOR
parents understand the baby's language — and jump accord-
ingly. For babies, as Watson says, enjoy such tyranny as is
rarely displayed by the crowned heads of history.
Endless repetition. Tryings out, tryings on. A slow proc-
ess. But fast time once a real start is made. "Dog" at
first means dog, also cat, also bone. The meanings of words
become restricted; the words themselves, whether spoken or
heard, more definitely conditioned. "Dada" gives way to
"doll" and "daddy." The baby's vocabulary is replaced by
parents' vocabulary. The useless and random sounds and
words disappear; those which bring results are retained.
The learning processes involved in conditioning the appe-
tite, using knife and fork, and taking food, are all the same.
A girl of twenty-eight months has a vocabulary of 400
words; a boy of forty-three months, 960 words; a boy of
fifty-four months, 2,000 words — enough to carry a moron
through life. The college graduate rarely knows more than
5,000 words.
Language is part of human adjustment, learned as other
actions or habits are learned. Every normal newborn has the
potential ability to learn to talk English, Kwakiutl, Chinese,
Zulu — any language. He learns one — English, let us say;
learns it well. At twenty it will be difficult for him to learn
French, more difficult to learn Zulu; by the time he is fifty
it will be very difficult, so difficult that few do it. English
is of little help in learning Kwakiutl: one goes head first, the
other goes feet first.
Each language employs certain phonetics and proceeds
after its own grammatical form. In learning English, speech
organs and ears are trained to English phonetics, to the rules
of English grammar. Over a hundred muscles are involved ;
delicate adjustments of an extraordinary complex mecha-
nism ; to say nothing of the tongue itself. This neuro-muscular
mechanism learns English: English is its habit. To learn
English phonetics, other hundreds of possible sounds and
375
WHY WE BEHAVE LIKE HUMAN BEINGS
word combinations have been neglected ; they can be rescued,
if at all, with difficulty.
A pair of chopsticks and knife-fork-spoon are about as
diflferent-looking objects as one can easily imagine. They
seem to have nothing in common. So with English and
Chinese, spoken or written. The two languages do not look
alike; they sound as unlike as cat and canary talk. With the
same inherent equipment of muscles and organs the child
learns to eat with chopsticks and talk Chinese if brought up
in a Chinese household; or to eat with knife-fork-spoon and
talk English if brought up where such eating tools are the
fashion and English is the mother tongue. Children of
English parents brought up in India or China often learn
first the manners of eating and the speech of their native
nurses. A resounding belch after the meal is "good man-
ners" in certain parts of the world. Manners are habits.
If the baby hears baby-talk, baby-talk will be its first
language, its mother tongue. It may never feel so much at
home in any other language. Even tones are learned. Every
child can learn to whine or talk through its nose, or to speak
in coarse or harsh tones. If such have value in the house-
hold, the baby will learn to fix their value. A dozen words
from a two-year-old may "speak volumes" for the house-
hold.
In hundreds of languages there is a distinct word meaning
water; and several ways of pronouncing "water" in English.
Why so many words for the same thing, so many ways of
pronouncing the same word? Each language has its own
short-cuts to verbal activity, its own verbal response to H2O.
You pronounce w-a-t-e-r one way, I pronounce it another:
we learned it that way. Having learned it that way, we
react to other pronunciations of "water" as we react to
other forms of behavior differing from our own. If we wait
until we are grown, we find it difficult to pronounce "Z'eaz^"
as the Frenchman does — or understand his idea of water. We
get set in our ways. Our vocal structure gets set in its ways.
376
ACQUIRING HUMAN BEHAVIOR
Especially the larynx. Between twelve and fifteen it under-
goes great structural change.
Removal of the larynx removes the vocal cords and so
destroys the capacity to speak aloud. But as long as an air
passage is open from lungs to pharynx and mouth, whispered
speech is possible. If the passage is closed so that one must
breathe through an opening in the trachea below the larynx^
there can be no whispered speech. Such cases are known:
they can speak neither in nor above a whisper; yet they learn
to make all the movements necessary for articulate speech.
From all of which Watson argues that thinking is action
in a certain motor mechanism, as winking is action in a cer-
tain motor mechanism. We think in words; words are lan-
guage mechanism activity. Hence, thought is language
mechanism in action. Destruction of enough of that mecha-
nism to make impossible any of the movements involved in
speech is to make thought, and probably life, impossible.
Certain phases of human culture certainly would be impos-
sible without language. Nor is any culture known without
its linguistic constituent. As Kroeber says, it is difficult to
imagine any generalized thinking without words or symbols
derived from words. Religious beliefs and certain phases of
social organization such as caste ranking, marriage regular
tions, kinship recognition, and law, also seem dependent on
speech. But it is conceivable that certain inventions might be
made and the applied arts developed in a fair measure by
imitation among a speechless people. How and why primi-
tive man alone of the Primates developed the faculties for
speech and culture remain a profound puzzle.
11
For over two years the child has been using words, but only
after two years' trial and error and constant effort and end-
less corrections can the child be said to have a well-organized
verbal behavior. From the age of three and on, word and
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WHY WE BEHAVE LIKE HUMAN BEINGS
kinestlietic organizations are put on simultaneously. By the
time we are four we have added to our kinesthetic and emo-
tional organization a third element of behavior: we can talk;
we can react with words.
We begin our word organizations early. We learn "ball"
and a ball. We learn what follows when we do not respond to
"Don't!" "Blow your nose!" "Stop teasing little sister!"
"Bad boy!" "Shame on you!"
Very shortly the infant's world is largely words — together,
serving as stimuli to call out reactions. The times without
end that we react to "Let that alone!" As a consequence we
come to answer a vast word-world with words. The word-or-
ganization dominates. The sensori-motor throat-mechanism
becomes the controlling segment of the body. The tongue
becomes gifted!
We can remember our games of marbles and ball, and the
birds' nests we robbed, and the early swims in the creek, and
the arrowheads we found, and the hundreds of actions per-
formed after three or four years of age, because we talked
about them at the time. How well we remember them depends
on the extent to which our word organization paralleled such
bodily actions and the amount of emotional reinforcement
accompanying such actions.
Thus, word organization that accompanied explicit body
organization plays two roles in behavior: we can always talk
about it, memory; we can by words begin, correct, modify,
or control the total reaction.
I can talk about learning to swim; I cannot talk about learn-
ing to walk. Learning to swim was accompanied by talk — of
swimming. Learning to walk was accompanied by bumps
and bruises — often vocalized but not verbalized. In later
years a bump on the shin or a fall on the ice generally finds
us speechless but rarely emotionless.
By the time we reach school we solve problems on paper:
build houses and bridges, explore the Amazon, cross Asia
with Marco Polo, conquer Europe with Napoleon, write
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ACQUIRING HUMAN BEHAVIOR
books, edit newspapers, make love to Dido. There is no end
to this verbal organization, no limit to our capacity to make
verbal response. Only memory sets the limit to the problems
that can be solved with words.
But we do not always say the word. The stimulus to call
a man a cur may be great: we repress it and "get hot under
the collar"; or to pronounce the name of a loved one: we
repress it and blush or giggle; or, think it over.
Every word of the 400 the girl of twenty-eight months
knows is a conditioned reflex. Her eye sees candy; her
mouth waters candy; her voice says candy; she says candy
until she gets it: all learned responses, all habits, all reflexes.
To say "candy" is an explicit act of behavior; it implies
stimulus, receptor-conductor-eff'ector. The eff'ector was the
voice mechanism, the speech organ. Suppose she had not
said candy but thought candy: would this have been an act
of behavior? Is thinking candy a reaction?
We talk to ourselves, some incessantly. We call it "think-
ing out loud." It is: thinking aloud. Many never learn to
read without moving the lips ; closer inspection of their throat
shows all the muscular movements involved in reading aloud,
except in the vocal cords. They move their lips because they
have never completed the transition stage between explicit and
implicit language habits, between talking and thinking.
Children talk; and keep on talking. They are responding
to stimuli. There comes the stimulus: "Keep still or I'll
..." They keep right on talking — but to themselves. They
learn the new habit of talking without articulating; the vocal
cords do not participate in the action. By and by they learn
to drop even overt lip movements. They can think the word
hunger without overt movement of any of their laryngeal-
throat-mouth mechanism. The taking on of such habits begins
early and involves no new or strange process either in learn-
ing or in the conditioning of reflex arcs. Almost as soon as
the child can talk it is told not to talk. But the child has
already learned to make adjustments with words. By trial
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WHY WE BEHAVE LIKE HUMAN BEINGS
and error it learns to drop its voice, to whisper, and finally
to dispense with all overt movement. It is now a real thinker,
A shrewd observer and a good lip-reader can read the thoughts
of others who have not learned to think except in overt move-
ment.
"Now think of something; think hard!" You think of,
say, beefsteak. To your chagrin and amazement, the clever
observer says, "You are thinking of beefsteak!" Try it on
yourself. But there are those whose thoughts cannot be read.
They can think without overt muscle contraction, so short-
circuited and abbreviated has become the habit. The ob-
server's eye detects no sign of movement, but could we apply
delicate instruments capable of picking up nerve impulses
and detecting faint muscle contractions, we should find that
thinking "beefsteak" differs from saying "beefsteak" only in
degree of action.
I enter a restaurant with my stomach crying food and
my mouth watering beefsteak and my throat thinking beef-
steak. I sit down in a chair. That stimulates the waiter: he
responds with ice-water, etc. But I want beefsteak. I can
make that want known by several methods: I can make a
picture of it; describe it; point to it on the menu or to a plate
of it on another table; or produce one from my pocket and
make signs of more. Any one of these methods might stimu-
late the waiter to action. But he is in the habit of respond-
ing to word stimuli. I say, "Beefsteak." That word spoken
within his hearing brings quick results. And with a beefsteak
I am adjusted — to food.
The chief business of thinking, as implicit language proc-
esses, is for individual adjustment. The supreme value of
language is as an instrument of adjustment in social organi-
zation. Because of language the situations which confront
individual members of society are extraordinarily complex
and infinitely varied. Most of these situations, or stimuli, are
word situations; we can adjust with words. Sometimes we
"Katy did!" "Katy didn't!" the whole night long.
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ACQUIRING HUMAN BEHAVIOR
Of course, we think with our entire body. Our entire bodily-
organization is at work: at times at a high rate, at times
low; at almost all times one part is more active than another.
Rarely do we get into action with our bodily organization
functioning as a unit and to the limit of its capacity. The
body thinks, now here, now there, and the responses are
always in keeping with the conditioned reflexes in implicit as
well as in explicit mechanism. We do not reveal all our
thoughts, nor always even think them in words to ourselves;
nor does an ameba or a cat. Our bill of inherited "rights"
is not less.
12
Man is a talking animal and because he can talk has in-
creased his response mechanism beyond measure. Most of
our adjustments are with words, and for most of us the
older we get the more we rely on words. Our verbalized
organization dominates our life. But our earliest and our
last responses, and many in between, are speechless, part
of our unverbalized behavior; we only look the part, by a
smile or a frown. Response without words is the more ancient
mode of adjustment.
Language short-cuts work and play and makes culture pos-
sible, but because of language we become complexly inte-
grated. Words become loaded. One word can set more men
marching to death than any one earthquake ever killed or
volcano drove from home. "Lend me five dollars" can lead
to action as overt as a wink or a kick on the shin. If "Lend
me five dollars" leads to explanations, the explanation re-
action is also overt.
To the thousand petty annoyances, discomforts, and sense-
less situations of life, few of us have any reaction beyond
words: "What a nuisance!" "Isn't it a shame!" "That ought
to be remedied," "Some day they will do better," etc., etc.
We pick our way about through the flotsam and jetsam of
stupidity and ignorance of yesterdays, without a move to
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WHY WE BEHAVE LIKE HUMAN BEINGS
clean up the mess beyond words, words, words. We grow
indignant and with clenched fists and flushed face exclaim that
we could show them what we etc., if etc. We have thereby
fought a righteous battle for the good of the cause. Words,
words, words. Even the air is full of words these days.
We bandy words as boxers spar for position. We play our
best golf in the club-house; turn the rascals out in hot argu-
ment in the smoking car; bring peace on earth good-will to
men at church ; and correct our bad habits and save up money
in bed.
If you will listen to me I can prove to you that I am an
expert golfer and that I am really interested in good govern-
ment: I can prove it with words. And if you are a good
fellow you will take me at my word; but if not, you will brag
about your golf and tell me what you would do if you were
President.
There are many star performers with their verbal organiza-
tion who rarely let their bodily motor mechanism get into
action: he-men who never fought a fight or played a game of
one-ole-cat, golf, or tennis in their lives; reformers who were
never in a voting booth.
Even talking wears some people out. They just think.
They are content to think themselves good golfers, good citi-
zens, good Christians. They think beautiful thoughts, poems,
pictures, music, peace on earth, etc., etc. Even thinking tires
some people. "In winter I set and think; in summer I just
set."
"Don't bother father; he's thinking." One might suspect
him of being asleep. W^at is father thinking with? His
mind? Is thinking action? If it is, and if he is thinking hard,
he will be consuming energy. There is no action without
energy. If father can think without energy consumption, he
should be removed to a museum where they keep mermaids.
After an hour "father" rises, puts out the light, and goes
to bed. That may have been his regular hour for bed. Yet
in that hour he may have done the "biggest day's work of his
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ACQUIRING HUMAN BEHAVIOR
life." He may have reached a decision "momentous" in his
own and his family's life. Great Scott! his decision might
affect the destiny of nations!
What was the decision? How can I know: he said nothing,
made no move or sign, no overt explicit act of any kind. For
all I know he may have decided to sell the car, give up smok-
ing, change his bootlegger, run for President, or declare war.
"Well, fellows, what do you think about it?" One nods;
one shakes his head; one turns his thumbs down; one shrugs
his shoulders; one winks; one whistles; one clears his throat.
The last "fellow" rises to emphasize his remarks: "Well,
fellows, if you ask me what I think, I say: Oh, hell! That's
what / think!"
The "fellows" usually voice what they think. One word
stimulates another: many cannot stop, once the first word is
uttered. We fight countless battles with words. With words
we fly to the moon and build castles-in-Spain. In fact, the
range of our activities is only limited by our vocabulary.
That is why we think so much: one word stimulates another;
we cannot stop. There is no problem we cannot wrestle with
in thought. Thinking is so easy, Watson calls it laryngeal
itch.
When our thinking is in words we are thinking "out loud"
or "to ourselves." The latter is silent laryngeal itch. The
stimulus for such thinking or silent verbalization need not
differ from any other stimulus to which other mechanisms or
higher or lower centers of the body respond. It is called itch
because we can make such varied responses to such varied
stimuli without "turning a hand" ; it is so much easier to turn
it over to the mind. "I will think about it."
The stimulus that sets us thinking may come from within :
hunger, sex, etc. More generally from without: anything in
the environment, from a house falling on us, to, "Come!"
And so we "think it over" in unvoiced words. If our
vocabulary is large we can think widely. But the poorest
of us can in our thoughts take journeys on yachts, endow
383
WHY WE BEHAVE LIKE HUMAN BEINGS
charities, win ball games, paint the house, kill off our ene-
mies, write novels, compose operas. Our only limit is words.
As there is a verbal substitute for every object in the world
the limit of the world we can carry about with us is set by our
verbal organization.
Father may have thought out a way to buy a new car, the
stimulus for such thinking having been any one of the count-
less stimuli which excite people to think new car. The family
will ride in the car when father says a word, nods his head,
or writes a check. It is the thinking that gets into the picture
that counts.
The stimulus of an empty stomach serves the newborn for
its first thought: it says it with certain general bodily move-
ments; two years later it says it with a specific mechanism
which makes a sound like "hungry." Sixty years later the
response may be the same, even though no ear can hear
the word of the man who thinks it. In other words thinking
may be kinesthetic, verbal, or emotional. If we are hampered
in our bodily actions we talk; if our verbal thinking is
blocked emotional thinking dominates us. The final act may
be an unverbalized "judgment" — which need not be a rational
conclusion but is likely to express our irrational dislikes.
In silent words we make countless adjustments. To think
it out is an implicit habit of response. There are also implicit
hereditary or instinctive responses, as in changes in respira-
tion, circulation, and the whole system of hormone secretions.
Explicit habits of response are eating with a knife and fork,
playing tennis, staying on good terms with one's own and
the opposite sex, etc. There are also explicit hereditary or
instinctive responses, as in grasping, sneezing, etc., and in
the emotional reactions in rage, fear, and love. If the solu-
tion of a thought-out problem is not translated into overt
explicit action, spoken or written, or other explicit bodily
reaction, there has been no adjustment: the world of environ-
ment is just what it was.
Man's responses are uniquely his own because he has so
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ACQUIRING HUMAN BEHAVIOR
many words to respond with, so many ways of modifying his
explicit instinctive responses, so many degrees of emotional
outlets.
13
We recall Mother Goose without effort, even long poems
of childhood. I have forgotten my Latin, but certain Odes
of Horace and that good old resounding Dies irce, dies ilia,
I do not forget. Not for twenty years had I thought of a
certain jingle. I find myself in the midst of some girls. With-
out warning, and to my surprise, I begin: "Briar, briar, lim-
ber lock ..." Where has this counting-out rhyme been
these twenty years?
There is no short-cut to learning, nor system by which the
memory can be improved. Goose, Odes, Hymn, and Briar
were learned, over and over: overlearned. We overlearn
many things in childhood we "never" forget. We learn much
in childhood we do forget.
Forgetting is in proportion to learning; the more we learn
it, the longer we remember it. Learning is a soaking-in proc-
ess. Some things must be learned many times before they
soak in. The idea that we forget the unpleasant or the pain-
ful because it is unpleasant or painful is nonsense.
We learn to swim in youth. If we began each spring where
we left off each autumn, we overlearned it. We can jump
in forty years later and swim. So with driving nails, play-
ing marbles, etc.
We know how to swim. But vivid swimming memories are
mostly accessories: the thrashings we received when we ar-
rived home, the knotted wet shirts, the frenzied efforts to dry
our hair. They were emotionally tied in.
Every reaction we make has its instinctive and emotional
background, its explicit and implicit factors. Rhymes, Bible
lessons, poems, particular conversations, etc., remembered
from childhood were emotionally tied in as well as over-
learned. The emotional factor is of great importance in con-
385
WHY WE BEHAVE LIKE HUMAN BEINGS
ditioning reflex arcs. In learning to swim, drive a nail, recite
a poem, these factors get tied together and work together.
They become so tied together that one of certain stimuli
can set them off. What was in the situation to set off, "Briar,
briar. ..." I do not know. It may have been one of a
dozen stimuli : the general situation itself, something peculiar
in the situation, etc. This is certain : my overt act in repeating
the jingle was in response to an adequate stimulus. We call
ourselves self-starters, but we start in response to a stimulus
whether to run, climb a tree, recite a poem, or think. There
was some stimulus in that situation which recalled past ex-
perience to me.
I had been there before, as it were. We often say that,
knowing well that we never have; and call it mysterious.
There is no mystery about it. Some detail in a situation,
in a room, in a man's face, vividly recalls some past ex-
perience. The recalled detail is so vivid that we feel we have
"been there before," have "seen that man before."
Memory does play strange tricks. But it seems less tricky
if we think of it in terms of situation and stimulus. WTien
we cannot remember our own name — and sometimes we can-
not— the situation is one in which we have had no experience
in remembering our name, or in which no adequate stimulus
is at hand to break through other stimuli clamoring for atten-
tion. Trying hard to recall it makes it hard for the adequate
stimulus to appear. The next morning the name may pop
into our head. The stimulus for recalling persisted; there
had been no adjustment. During sleep or on waking the
adequate stimulus gets a hearing: the name "pops into our
head."
As did "Briar, briar. ..."
Between the years we learned to swim and the day forty
years later when we jump in again, arms and legs learn no
new habits which make swimming mechanism hard to func-
tion.
The childhood lessons that are forgotten were never over-
386
ACQUIRING HUMAN BEHAVIOR
learned or were built into other learning. We remember our
A B G's because we continue to use them. But of the stories
in the Readers we remember only our favorites. The count-
ing-out rhymes were repeated so often — as was Dies irce —
that the conditioned reflex chain was grooved. "Ene" was
adequate stimulus for "mene," and so on.
It requires longer to learn "Ura, eyuk, ro, duni" than to
learn "Ene, mene, mine, mo." "Ene mene" does not make
sense, but it jingles. It requires ten times more practice to
learn nonsense than sense material. And the longer the non-
sense series, the longer proportionate time required; each
syllable must become tied up with the one preceding. Hence,
nonsense syllables are quickly forgotten. To relearn them
eight hours later requires two-thirds of the original learning
time. There is no such forgetting during the intervals in
learning to play the piano or the typewriter.
Boys quickly learn to swim; it becomes a habit more
easily than skating. No school in summer. One habit is
learned more quickly than two. Learning lessons in school
formerly progressed slowly: practice periods too close to-
gether, too little incentive.
We can learn only so much of any one thing in one day.
But between times we can learn something else. If it is a
poem, game, or complicated process, we learn it more easily
and remember it longer if we learn it as a whole. The way
to learn Paradise Lost or a part in a play is not line by line,
but as a whole. When learned as a whole it is remembered
as a whole; when learned line by line it is so remembered:
it is not so well tied in. We know a thing "by heart" when
our memory anticipates every reaction in the chain.
It is the stimulus that counts. Rats, mice, guinea-pigs,
birds, and cockroaches learn to thread an elaborate maze;
even at the cost of pain if the stimulus be adequate. Hunger,
for food or for the opposite sex, is the stimulus used. Old
rats require longer effort and more trials to learn to thread
387
WHY WE BEHAVE LIKE HUMAN BEINGS
the maze. But no rat has yet been found too old to learn
to thread it!
Within reasonable limits, youth learns more rapidly than
adult age; both learn in proportion to incentive to habit
formation and uniformity of height of incentive. A man is
as old as he is incapable of learning.
We learn only if we have the incentive. But even the
reflex time of knee-jerk slows up if repeated at once. A
joke told is already stale, good thereafter only to the teller
when he can find new victims. One lesson was enough for
Eve.
Memory is looking backward; of biologic service when it
impels us forward.
14
"Don't jump; diveP^ Easier said than done. We are
organized on head-up, feet-down plan. We learn to walk
that way. The first dive is a new experience: it reverses
our feet-down head-up and away-from-solids habit; the
water looks hard; there may be rocks below. There were.
The boy never forgot it — nor learned to dive. No will power
inside his skull could cause the nerves outside to forget their
lesson. He could not put his whole heart into a dive.
Some boys can; they have the do-or-die habit. They
explore bottoms and dive in again. And again. By the end
of the week they dive like frogs. Their sisters are just as
good. Do-or-die for one is usually do-or-die for all in tlie
family.
The boy who learned to dive in spite of his first mishap
succeeded largely because of it. The problem was different,
more difficult than he had anticipated. That tapped a new
source of zeal. He became a high diver in the circus. A
net is not water, but the skill required in maneuvering a
head-first body in diving was available in learning to dive
from the top of the big tent.
There is always great complexity of stimuli in any given
388
ACQUIRING HUMAN BEHAVIOR
situation; the situation itself is always changing, A pig
quietly nosing along a swill trough is joined by two more
pigs. New situation now: the first pig gets into the trough.
The family have just sat down at the dinner table. The
door bell rings. Behavior of the entire family changes:
mother jerks off her apron, father puts on his coat, sister
wipes brother's mouth, brother kicks the cat. New situation;
only one new stimulus, door bell. The family jumped to
the reaction: well trained.
Baby alone went right on banging his spoon on the arm
of his chair. Baby had just acquired that habit and found
it so stimulating that entrance of stranger did not alter its
situation. But the family now are suddenly conscious of
baby's behavior. Mother asks sister to take baby into the
kitchen, knowing that removal of spoon will set off the first
habit baby learned (crying till he gets it). Baby is not
likely to lose that habit: no other one yields him such large
returns.
We become Dr. Jekyll or Mr. Hyde. Few can become
both. We have our own level of organization, our habits of
response to situations in which we feel at home. But Jekyll-
Hyde was at home in two situations. His was a dual per-
sonality. In one set of situations he was Dr. Jekyll, in the
other Mr. Hyde.
There are times when, to our astonishment, dog or child
makes no response to name or other stimulus which ordinarily
calls out a response. If we cannot predict a child's response,
how can we expect to predict the behavior of an adult? How
can we know when Mr. Hyde will turn into Dr. Jekyll?
We cannot. Even prediction of a comet's movements is
simple compared with predicting the behavior of an ameba.
But there are some general principles that are of general
application.
Our response to a kick on the shin may be: "Well, I'll
be . . ." That response does not follow if we are in church,
even though the kick came from the same brother. The
389
WHY WE BEHAVE LIKE HUMAN BEINGS
situation as a whole is a determining factor. The response
is delayed until the situation is right. In Rome we do as
the Romans do. Ditto in church, at a ball game, at a ball.
The response is likely to be a repetition of one recently
called out. We have not been to a movie for months: a
friend drags us out; we go to a movie every night for a week.
I have just visited a maple-sugar camp: I now notice maple
trees everywhere ; and see sugar cakes in the grocer's window.
I passed them by this morning without noticing them.
A fire engine shrieks through the street several times a
week. I have long since ceased to notice it. I do to-day:
my fire insurance expired yesterday. I am all excited
because I intend to listen-in to-night: the President's speech
is to be broadcast. I make certain that my radio is in order.
At eight o'clock I have the colic: the President's speech means
nothing to me.
My response to a knock on the door may be to open the
door; I may lock it, turn out the light, and reach for a
revolver. I may pray. Vast numbers of our responses are
made with words. This doubles our response repertoire,
complicates our behavior.
Four brothers — a banker, a preacher, a paleontologist, and
a bootlegger — read the news of the sinking of the XVIIIth
Amendment: predict the response of each. The door bell
rings, a man enters; it is their enormously rich Uncle Bim
from Australia. The situation is again changed. But to
each and to all situations an almost unlimited number of
varying responses was open to each of these four men. And
is open to all of us.
There are also two ways of clothing our nakedness — for
we are born naked and are not ashamed of it. But the over-
dressed man and the underdressed woman had the same start
and are only happy when they are noticed: on the stage or
platform, or in the pictures or a lodge parade. When a
woman cannot make an exhibition of herself any other way
she can start a dress-reform movement.
390
ACQUIRING HUMAN BEHAVIOR
Human beings, acting and reacting. The situations which
call out reactions are diverse. The response any given indi-
vidual will make to any given situation is a variant and
depends upon that individual's previous experience, includ-
ing such things as cold toast that morning, the reading of
The Marble Faun ten years before, a fight twenty years
before that. Individual behavior.
Yet, as Watson says, it is almost impossible for a balanced
man to be so torn as to steal his neighbor's purse or child,
or to commit suicide or mutilate others. Such responses are
possible only to the extent that the co-ordinations used in
committing such crimes are in his behavior repertoire.
Furthermore, his total reaction systems are so tied together
that the moment he starts to commit suicide or a crime a new
situation is created and leads to a different act. It is quite
impossible for most of us to commit suicide; our conditioned
fears and our unconditioned responses will not let us. Prac-
tically all our suicides are pathological — diseased personal-
ity. Suicide in Japan or China may be normal behavior.
We are not mosaics of inherent reflexes and learned habits,
but we are going concerns. How we go, how fast we go, and
what we go in or out for, depend on the situation and our
experiences with previous situations. "We act in line with
our training and in conformity with our inherited points of
weakness and strength." The situation we are in dominates
us and releases one or the other of our all-powerful habit sys-
tems— we exhibit our learning in the manual, laryngeal, or
visceral field. A cross-section of our habit systems in these
three fields gives us a picture of our personality.
15
We learn new responses for adjustment purposes and in
taking on habits are subject to factors which condition all
learning. We become adapted, positively or negatively: the
391
WHY WE BEHAVE LIKE HUMAN BEINGS
stimulus reaches us more easily or we inhibit it with less
effort.
A doctor asleep beside his wife hears only the telephone;
she hears only the baby. But if the baby cries long enough
he will hear it, and if the telephone rings long enough she
will hear it. There is a limit to adaptation. Both can hear
a mouse or a burglar. Most boys can hear a penny drop;
most men's ears pick up nothing less than silver.
Tight shoes are only tight until we get used to them. It
is the sudden drops in the temperature that we notice. We
grow accustomed to change if it is gradual: bad air, bad
food, bad government, bad wives, bad husbands, bad chil-
dren, high cost of living. Life can make huge concessions
if it is not crowded or pushed. As long as the breaking
point is not reached, we can stand it. Wives at fifty will
look just as good as at twenty — if the change has been
gradual. We can become adapted even to lethal doses.
When any given stimulus sufficient to set off the response
mechanism is repeated, the threshold is lowered and the
response hastened: we are positively adapted, favorably dis-
posed. We are negatively adapted if the stimulus is grad-
ually increased without increased or with delayed response,
or if the threshold is permanently raised. If we fail to get
up with the alarm clock we soon fail to hear it.
We have a "hangover" after intense and emotionally
stimulated activity. After a long session at cards, our minds
go right on playing cards. We "pop the question" on a
moonlight night after a preliminary warming up. Warming
up lowers the threshold and has psychologic value in all
fields of activity where we are out for victory.
Why do we like certain poems, pictures, songs, melodies,
hymns? I sat through a Georgia camp meeting recently.
The preacher exhorted and exhorted; no one came "forward."
Then another old familiar air was set in motion: many went
forward.
Leaders — in religion, politics, and business — get "results"
392
ACQUIRING HUMAN BEHAVIOR
because they know how to play on us. We buy or bite not
according to our requirements or on the strength of the
merits of the "goods" they sell us (for they rarely talk
merits), but according to their appeal to our attitudes.
We go to a political rally. Flags everywhere; pictures
of Washington and Lincoln on the stage. That stage is set
for us; the trap is baited. We do not need these settings;
but they do their work: they make us favorably disposed.
We cannot look at Our Flag or the Father of Our Country
without being moved. Prayer follows: God, save America
and bless the man who is about to save it. Etc. Then the
speaker talks about Lincoln and drags in other matter
irrelevant to his own fitness. And we are further moved.
And with an, "All together!" we sing "America." That
decides us: he is the man we want.
The successful politician may never have heard of "emo-
tional tendencies built up through association processes" or
of "conditioned emotional responses," but he does not try
to sell himself to a Georgia rally with a eulogy on Sherman
or ask all to rise and sing "John Brown's Body." Nor does
the salesman try to sell refrigerators to Eskimos or the com-
plete works of Darwin to South Carolina.
Whether we are positive or negative all depends. But we
are positively adapted for anything and everything that
interests us. Whether a particular thing is to our interest or
not also depends. We can learn.
16
The principle back of breaking habits is the same as that
back of forming them: substitution. Substitute another.
Sometimes it is difficult; the path may be worn too deep.
Then it is a habit: if useless, a bad one; if dangerous, lock
him up.
A farmer breaks a colt gradually. He accustoms it to the
sight of things, to the feel of things ; little by little. The first
393
WHY WE BEHAVE LIKE HUMAN BEINGS
thing the colt knows, it is hitched up. It is broken to har-
ness. But a colt can have its conditioned fear reflexes. And
when the stimulus comes — umbrella, locomotive engine,
auto, red dress, any fool thing — it scares. One way to keep
it from scaring is to keep it away from fearsome things. A
better way is to condition it to men. With fear of men gone,
the colt begins to have confidence when there is a man about.
The human infant has almost no specific fears. Its par-
ticular fears become conditioned and terribly real. They
can be conditioned out, gradually. The old habit of being
afraid of certain things or persons is replaced by other
habits.
As the weaning day approaches many babies take to
thumbs. The thumb satisfies the sucking reflex, an instinctive
act. But if the baby is not allowed to get its thumb in its
mouth, the sucking reflex will disappear along with other
infantile actions. Elimination functions are instinctive and
many habit activities are built up around them. Such acts
cannot be broken up, as can the sucking reflex, but they can
be socialized and the infant can be taught continence with
respect to them very early in life.
Habits, whether inherent or acquired, can usually be
broken up by altering the stimulus. Horses often show their
fighting instinct by kicking or biting at a passer-by. But a
horse which has bitten into a sleeve of cayenne pepper is not
likely to bite into another sleeve. If the figure passing
behind him is a dummy, and if his feet are jerked from
under him as he kicks at it, he will think of his feet the next
time he is impelled to kick. The dog which instinctively
sucks eggs loses his appetite for eggs after he has crushed
a cayenne pepper prepared egg. The instinctive chain
reflex now reads: smell egg, hang out tongue to cool; instead
of : smell egg, crack it, lap it up.
Specific fears and other forms of emotion generally run in
families; they are handed down, conditioned in. Children
of lion-tamers, snake-charmers, steeple-jacks, etc., grow up
394
ACQUIRING HUMAN BEHAVIOR
without conditioned fears of lions or snakes or high places.
The son of a snake-charmer may go in for the ministry, but
the minister's daughter is not likely to become a snake-
charmer.
The child that has everything it wants is no more likely to
form habits of thrift than a Hottentot or a monkey. Habits
are not formed by uttering precepts. Nor is moral conduct
founded on preachments. Nor a bad habit broken by warn-
ings. But a little common sense and a few lessons in the
biology of reproduction have not yet been known to encourage
youth to bad habits and have been known to make for sanity,
peace of mind, and normal behavior. Much of the drive
behind morbid curiosity in the young springs from society's
ban on such matters. The ban itself only makes a natural
curiosity morbid and adds zest to the gratification of that
curiosity.
Our erogenous zones, as Ellis calls them, function from
birth: they respond to stimuli. The baby can gurgle and
coo and smile when it is tickled or patted or pleased. The
hug response follows the outstretched arm movement. Just
where love comes in it is not easy to say. It does come —
early; it does get conditioned into our emotional fears and
hates, strengthening them, modifying them, coloring them.
Especially into our attitudes, even toward a sunset. Our
emotions get more or less saturated with sentiment. Often
the mate-hunger impulse receives more than its share of
rebuffs. These lead to definite attitudes backed by emotion.
The lovesick maiden seeks sympathy and the lovelorn
youth solitude. And few there are who do not know the
meaning of shame, envy, hate, jealousy, shyness, embarrass-
ment, pride, suspicion, anxiety, anguish, resentment, etc.;
emotional habits conditioned on to instinctive tendencies.
They upset us in dozens of ways ; they make or break or pre-
vent marriage; they are as much a part of us as our arms
and legs.
395
WHY WE BEHAVE LIKE HUMAN BEINGS
Emotional attachments are of value only when attached
to serviceable or useful behavior, when called out under
stress, and when directed to the big business of life. It hurts
to be scared and we boil when we are enraged. But the life
that always boils or is scared cold has little time for routine
business of life.
The time to break such hurt and boil habits is before they
are formed: before the emotions have become specific for
things, places, and people that are not changed by tears or
smiles. Then we can talk of moral and political issues with-
out slopping over into useless sentimentality or boiling over
with worse than useless vindictive animosity.
This is not easy. It is easier to allow our emotions to
move us than to restrain our emotions and inquire : where do
we want to go and why do we not move in that direction?
Easier, because that is our habit.
17
Your family physician can put you to sleep with a drug,
but he cannot tell you why you suffer insomnia or why you
can walk in your sleep. Or why you sleep — or wake up.
One popular theory solves the problem with thyroid hor-
mones. Muscle activity generates poison — "fatigue prod-
ucts." Iodine is anti-toxic. The thyroid furnishes iodine.
Hence . . . But inasmuch as the infant sleeps early and late
and cannot be presumed to have generated much fatigue
product from muscle activity, sleep itself was assumed to be
instinctive biologic defense mechanism to prevent intoxi-
cation!
Which explains sleep just as much as breathing is
explained by saying that we breathe in order not to become
asphyxiated. We cannot commit suicide by holding our
breath, nor by withholding our sleep. Breathing and sleeping
are reflex acts which travel on their own. The muscle toxins
396
ACQUIRIXG HL"MA\ BEHAMOR
were assumed. It was then presumed that the th^Toid — or
some other gland — washed them out.
The vasomotor theory- assumes that at the end of tlie day
the center of the nervous system which regulates the size of
blood vessels gets "tired.** As a conse-ijuence the blood sup-
ply to the brain is panially cut off. That puts die b:.ii.: to
sleep. Then we sleep.
But is the brain robbed of blood during sleep, does action
in skeletal muscles lead to intoxication? In other words, is
there any basis in fact behind the commonly accepted theories
of the cause and f miction of sleep? \rhen we are tired we
fall asleep more easily than when we are fresh. But the
loafer does not have to be tired: he drops off to sleep at his
regular hour — or any odier hour. \or is the brain robbed
of its blood during sleep: the evidence points the other way.
But whether the brain has little or much blood, die vasomotor
change may be the conse<:pience as well as a cause of sleep.
Neither explains the release of die sleep reflex.
Kleitman and Lee. working on a human subject kept a^vake
for 115 hours, could find no evidence of g- ' ^ - - •
either in the carbon dioxide content of th- .
sugar, heart rate, respiration, temperature, or rate of basal
metabolism. The theon.' of in: : : -^:'?n at the end of ever\-
sixteen hours falls flat.
Their experiments uncovered other facts at variance widi
popular notions about sleep, especially as to die efl'ects of
loss of sleep. After nearly five days without sleep, the sub--
ject showed no variation from the normal in a larg- r.ijer
of functions. He ate and worked as usual. His knee-kick
and eye-pupil dilation reflexes vrere unaff'ected. So was his
ability to do mental arithmetic, to name opposite^, and to
react to eye and ear stimuli. There vras no change in his
sensor}- threshold for electric-current stimuli. He did lose
some control of the muscles of his head: it wobbled. But
that may have been due not to insomnia, but to tired neck
muscles.
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WHY WE BEHAVE LIKE HUMAN BEINGS
The subject could keep awake only by continued activity.
An attendant accompanied him to prevent him from relaxing.
Whatever causes sleep, its onset begins with complete relaxa-
tion of the skeletal muscles. As muscular activity invariably
accompanies and is perhaps the most characteristic feature
of wakefulness, the probable cause of the onset of sleep is
relaxation, voluntary or involuntary.
Sleep itself may be due to fatigue of the highest centers
of consciousness; but whether to loss of nutritive substance
in the nerve cells or to increase of waste of cell metabolism
is not known. The highest centers are those of learned con-
trol and association of motor and speech mechanisms. They
are the most recent acquisitions to the nervous system, the
least organized at birth, the most modifiable from birth. A
small dose of alcohol affects the voice, a larger dose affects
the gait; but only a large dose paralyzes the respiratory cen-
ter: that is a low center.
In all the experiments performed, the subjects could not
study after one night's loss of sleep. They could do labora-
tory work and mental arithmetic, etc.; but their highest
centers gradually lost their irritability, as ours do after a
long day's work. Sleep restores this irritability. But just
what else happens during sleep is not known.
Dreams, for one thing. During light sleep sensations from
the viscera or from outside the body may reach lower centers;
they are older, better organized; presumably less subject to
fatigue. Dreams are not critical. These sensations do not
reach the highest levels of the cortex where only they can be
correctly analyzed and interpreted. If they become so strong
as to force their way into the highest level and rouse it to
action, we wake up.
Sleep, then, takes the kick out of stimuli that in waking
hours would receive attention and result in voice, thought, or
motor mechanism reaction. But the sleep-walkers! Their
dreams get into their high-level motor mechanism and they
398
ACQUIRING HUMAN BEHAVIOR
walk! Why walking does not wake them is not yet known.
What wakes us? Stimulus from stomach, bladder, or
other visceral organ finally becomes so powerful as to break
through synaptic resistance and rouse the cortex. We are
awake.
Why do we sleep? What is back of sleep?
But, first, what is back of life itself? Sunlight. The sun
is the primary source of the energy of green plants; in sun-
light they build up their bodies. But the light fails, the sun
goes down. They had to meet that condition, to find the
energy required to prolong life throughout the night. The
problem was met in two ways: by living more slowly — that
is, consuming less energy — during the night; by deriving
energy from breaking down and so releasing the stored
energy of their own body. Process of katabolism, or
destructive metabolism.
Katabolism, then, is an adaptation to the dark.
Throughout the ages since life evolved, day follows the
night. Throughout the nights, the machine of life slowed
down; it could not build up its body, but it couldl keep it
alive until the day came, the body itself furnishing the
energy.
We eat; the sun goes down; we go to sleep. The sun
comes up; we wake; we eat. During sleep the processes of
metabolism, especially the katabolic, continue.
Ages ago, our ancestors did not develop electric organs or
lucif erase ; they did develop diurnal habits. The nights were
given over to the vegetative processes, the days to action in
the motor mechanism. Having nothing to do at night, they
went to bed. There was no other place to go. With no
electric light to switch on, the wires to and from the highest
brain centers were switched off. Sleep became a habit. It
worked like a conditioned reflex, sunset setting it off. Even
to-day, some find it hard to break the habit; they go to bed
with the chickens and are up with the dawn.
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WHY WE BEHAVE LIKE HUMAN BEINGS
18
Judging from their behavior, all our four-footed friends
dream. Presumably their dreams are as unique as are their
individual selves. I find no explanation for my dreams that
does not take stock of my experience. Dreams themselves
are no more mysterious than is any other phase of adjust-
ment. Dreams and sleep are processes of adjustment based
on physiological processes.
It is assumed that dreams have a biologic function. "It is
the dream that really keeps us asleep," says Humphreys. He
cites the sleeper and a lawn-mower outside. The sleeper
dreams he hears something else: if he "heard" lawn-moiver,
he would have to get up and go to work. "He can only con-
sistently go to sleep by hearing noise as something else than
the sound of a lawn-mower."
That explanation is too simple; it covers too much ground.
True, many dreams seem to have the function of guarding
sleep. But to say that the dream keeps us asleep is as lucid
as to say that sleep causes dreams.
There are dreams and dreams, and sleep and sleep. Some
animals and people are always dreaming; some seem never
more than half awake. But inherent in life and human
beings is the necessity to "come to" when life is imperilled.
When now I lay me down to sleep, what do I lay down?
Obviously, not the same body that I carry to a Harvard- Yale
football game. But the body that carries me to the game may
be any one of 80,000 bodies in the Bowl. When half of them
groan the other half cheer. One particular body may sob,
another go into a frenzy of delight; another may yawn and
say, "What a rotten game!"
The body I lay down may be so tired it is "dead to the
world" and beyond stimulus of smoke, though my own bed-
clothes are on fire from my cigarette. I do not come to until
fire stimulates my skin. No dream kept me asleep, nor did
nightmare arouse me.
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ACQUIRING HUMAN BEHAVIOR
I may be very tired and yet wake at the low gentle gnawing
of a mouse. I curse the mouse and try to go to sleep again.
Why could I not have dreamed of squirrels in the wood
gnawing nuts and have slept peacefully on?
I have worked late and am tired. I must be up and at
work again within five hours: I need every minute of my
sleep. I drop asleep, and come to with a start. I have had a
horrible nightmare. I can sleep no more that night. I can
discover no excuse for my nightmare: no fire, no mouse,
everything quiet.
No excuse.
I sit in my chair on deck in the sun: not asleep, not think-
ing, not daydreaming. "Without a thought in my head." I
feel that I could sit there forever, the day is so fine. Sud-
denly I am up and off. I go to my cabin and write for hours.
I do not hear the dinner gong. The steward brings hot water;
I do not notice him. He now knocks twice before I hear
him: "Not going in for dinner?"
I may know, I may not know, what brought me up out
of my chair and started me to work. But when because of
drugs, alcohol, or toxins, we are quite beyond reach of mes-
sages from without or from within, we have passed out. But,
as a rule, we are as little conscious why a particular thing
pops into our head as why we have a dreamless sleep, or a
silly, lascivious, or nightmare dream.
Sleep is primarily relaxation — general dropping off of
the motor mechanism. But activity keeps on, though slowed
down a trifle, in the digestive, respiratory, and circulatory
systems. The bodily functions continue; the motor mecha-
nism goes out of action, including external receptors for out-
side stimuli. Consciousness quits, the mind stays on the
job. Consciousness is a functioning of arcs of the cortex of
the brain, where knowledge is stored and sorted. When cer-
tain parts of the cortex are injured — by disease or wound —
we lose control of something, as though we had quite for-
gotten. It may be use of part of the motor mechanism, or
401
WHY WE BEHAVE LIKE HUMAN BEINGS
the speech mechanism, etc. But with the cortex out of action,
we forget what we have learned.
Roused from deep sleep with the porter's admonition:
"Gotta get outa here in five minutes," we make a mess of
dressing. Seems as though we have forgotten which shoe
goes on which foot, and we blink at collar and tie as though
we had never seen such things. We are not "in possession
of all our faculties."
Hence, dreams mix things up. The right shoe on the left
foot. A shirt means nothing. And we wake up the next
morning with the "funniest dream; can't make head or tail
of it."
Or, the nightmare wakes us up and finds us in a cold
sweat. Nightmare behavior is jumpy behavior. The child
terrified at dusk by goblins and ghosts and Red Riding-Hood
wolves, carries an easily terrified body to bed and may carry
it for eighty-odd years: jumps at every sound while awake
and in sleep is subject to nightmare. Such a body is always
prepared to jump, until its hypersensitivity is educated out
of it. This is not an easy process if the early fears have
been branded in.
A dream may be anything. If A's dreams are wish- fulfill-
ments, A apparently is a Spanish-castle-builder and keeps at
it in his dreams. If A's dreams are also sex, it is because
A's mind dwells on sex. As wishes and sex enter into many
lives, they are likely to enter many dreams.
Sometimes the frankness of our dreams amazes us. Life
is frank. With the cortex out of action, we lose the guardian
of our morals. The mind of the dreamer rambles around
aimlessly and shamelessly. For the same reason scientists
often solve problems in chemistry, mathematics, etc., in
dreams; their mind was free from inhibitions, it was not
afraid to try out new combinations.
We solve many different problems of conflict just before
we drop asleep, or we drive them from our head long enough
to fall asleep. That problem is likely to form the subject
402
ACQUIRING HUMAN BEHAVIOR
of our dream: the body mind carries it on from the point
where it was dropped by the conscious mind.
Children and morons do not solve problems in chemistry
in their dreams. As in waking states, they deal with the
simple affairs of the day or of yesterday. Adults' dreams
may drop into childhood imagery and symbols. Starting
with some unsolved problem or conflict of the day, the mind
drops into earlier levels of mental functioning. Few of us
go through the day without some early memory rising up
like a ghost or blissful experience to haunt us or make us
sigh for the barefoot days. In sleep the mind wanders, and
easily and naturally into childish things or into childish
methods of playing cars with four chairs, one dog, one cat,
two dolls, and Johnny for engineer and Mamie for conductor.
"My dream has come true!" Often they do. As I write,
my body's mind wanders fore and aft and up and down.
It will be surprising if it can anticipate nothing of my
behavior or my family's behavior to-morrow or next week.
When our dreams do not come true — and generally they do
not, for truth has little interest for dreams — ^we say nothing
about it.
"Prophecy lies in my name, saying: I have dreamed, I
have dreamed."
19
We land at Bombay, deposit our belongings at the hotel,
and start out to see the sights. We need not move a foot:
there are sights all around us. All is new; nothing seems
like home. The very atmosphere has a peculiar odor, a
different feel. The sun is not the same. The houses, trees,
birds, shops, signs, noises, voices, cries, cattle, carts, car-
riages, trams, are different. Swarms of human beings unlike
any that we know; different in face, build, gait, dress,
coiffure, foot and head gear, and personal adornment.
Bombay is a new world. Nothing in our past experience
has prepared us for it. Suppose we have come to settle
403
WHY WE BEHAVE LIKE HUMAN BEINGS
down in Bombay? We realize that we have much to learn —
more than we can realize at first. We do not know how to
act. Wliy does that man stare at me that way? What is
the meaning of such behavior? We have no ready-made
behavior by which we can adjust ourselves to their behavior.
Even the flies, bugs, and insects are difl"erent. How are
we to know which are harmful or dangerous? At the edge
of a park we meet a little green snake. It appears harmless ;
it may be deadly poisonous. How can we know?
How do we? How do we know the world outside our skin?
We enter the native market. Piles of strange vegetables
and fruits. But nothing that we know. We see only certain
shapes, sizes, colors. But what are they inside — sweet,
bitter, mushy, hard, juicy? We do not know them. Our
mouth does not water. Suddenly we espy a box of peaches.
Our mouth waters now. We have a very clear knowledge
of peaches. A rat runs out; we jump back. We have not
seen a rat for forty years, but we have not forgotten rats; nor
that a rat is not to be caught with the bare hands as a rabbit
may be.
The first rat we met bit us ; the first rabbit we met we ate.
I know more now about rats than the mere fact that they are
ugly and are to be killed only at a safe distance; and about
rabbits than that they are harmless, defenseless, nice, and
good to eat. But there was a time when "rat" meant no
more to me than "hat"; or "rabbit" than "Babbitt"; a time
when neither a rat nor a rabbit meant more than something
which could stimulate my eye and provoke my reaching for it.
Because we are impelled to reach, and when within reach
explore, and because things either bite us or we bite them,
we do learn.
The world we know is the world we explore with our
fingers, tongue, eyes, ears, nose, and all the receptors widi
which our body is so abundantly supplied on or in die surface
or within. We know some objects, beings, qualities, and
quantities, well; some, not so well. Included in this knowl-
404
ACQUIRING HUMAN BEHAVIOR
edge of objects are attitudes toward objects. We learn
eventually to let sleeping dogs lie, and many objects, persons
and situations alone.
Don't monkey with that!
But we do. There is more monkey than rabbit in our
inheritance. As a result, a lively boy or girl of fifteen years
knows as much as the "average American."
'Ms there anything that child does not want?" asks the
harried mother. The child replies, "Nothing." And the
child that cries till he gets it answers: "Why not? Wliat are
things for if I am not to be allowed to examine them?"
It is a slow, complicated process, but after the child can
walk it goes on at an astonishing rate. Tireless, insatiable,
indefatigable youngsters! "If I didn't stop them they would
tear down the house and burn up the barn." Why not?
They might build a better one, or learn a new culinary art,
as Charles Lamb says the Chinese learned roast pig.
Here is a baby. It has learned the location of its eyes,
ears, nose, and toes, and can reach and grasp and handle.
Assume that it has been "carefully guarded" — which usually
means it knows next to nothing. Offer it a peach, pin, stick
of candy, match, red-hot poker, cat's tail, firecracker; same
reaction: baby wants it. It may learn enough in one lesson
to alter its behavior thereafter to each of these objects. Why?
Because hot pokers, firecrackers, cats' tails, pins, candy, etc.,
have their own behavior. Sooner or later baby learns that
the tail of a cat is not a handle to a plaything.
The first peach baby meets is, let us say, through the eyes.
Mere visual stimulus was enough for the first lesson. The
peach did not explode or bite or burn. Baby explores
further. Peach can also stimulate the skin of hand or body
or face; also the nose, the tongue, and sense organs in the
alimentary canal and kinesthetic senses. By the time the
exploration is complete the child knows a peach. Through
the responses to the many diverse stimuli a peach can make,
405
WHY WE BEHAVE LIKE HUMAN BEINGS
the child knows more or less of its color, shape, weight,
hardness, odor, taste. That it has a skin, that the skin is
tough and covered with down, that the down is unpleasant
to skin of hands, face, mouth, and tongue, etc., etc.
Knowledge of peach was built up. Visual stimulus was
adequate to provoke grasping response; odor stimulus pro-
voked another response; and so on. By and by any one
stimulus may call forth all the responses of all the other
stimuli, because these responses are conditioned. While
seeing peach, nose smelled peach, hand felt peach, tongue
tasted peach, etc. Until at last the mere word "peach" on
an empty tin can in the middle of a desert can be felt, seen,
sniffed, and tasted— there may be no peach within a thousand
miles. The response to the label on the empty can might
also lead to verbal response, such as, "Fd give a thousand
dollars for a peach," or, "I wish I hadn't eaten these
peaches," or, "You are a peach!"
The kick-back, the response the object itself makes to our
exploration, is not only part of our knowledge, but largely
determines whether we shall "pursue the subject further." A
child reaches out for a dog's tongue or a cat's paw: a bark,
a meow, a bite, a scratch. If bite and scratch are serious,
and especially if mother yelled, "Don't!" at the top of her
voice, we are likely to know barks and meows, and when
such melodies stimulate our ears we do not need sight of
dog or cat to complete our perception.
We learn Bombay that way. We sample the fruit and
vegetables, exchange our "good iron" dollars for their
"funny paper" rupees, and take no chances with snakes.
Learn to love mangosteens and how to eat a mango. Learn
to distinguish Parsee from Moslem and both from Hindu.
Get used to the idea of burning cowdung for fuel, and do not
shudder when we pass the Burning Ghats. Etc.
We learn life that way — building it up, building it up.
We know some things well. Many things we do not want
406
ACQUIRING HUMAN BEHAVIOR
to know; they bit us. We can even land in Bombay and walk
through the city concerned only as a dog would be; in which
case there would be other dogs, cats, places for food and
drink and sleep, and endless things to be avoided lest one
get run over.
Knowledge is power, no doubt; but what does it turn? Let
society answer that question for its own collective and indi-
vidual self. But what I know and what you know is that ice
is cold, fire is hot, rock is hard, hills are high, stars are far,
candy is sweet, vinegar is sour, rain is wet, wet paint comes
off, wood burns, he is a good fellow, rubber stretches, decay-
ing flesh stinks, roses have thorns, money talks, shoddy is
shoddy, fleas bite, glass is smooth, mules kick, bulls bellow,
roosters crow, corners are sharp, eggs are high, he is a scab,
she is worth looking at, Tut-ankh-Amen is dead, the razor is
dull, they are wearing them higher, all is not gold that
glitters, babies are nuisances, parents are easily led.
"How do you know he won't lend you five dollars?" "I
asked him: I know."
That kind of knowledge is power.
When the engineer turns the steam on he knows how the
steam will behave. He has monkeyed with steam, he can
anticipate its response. When the navigator leaves Aden he
sets his course for Bombay. He knows the behavior of his
ship, his compass, and the sea. At a certain hour of a certain
day he expects to sight a certain light.
Education does not begin at six; like charity, it begins at
home, and at birth, and should never stop. But it is equally
important to realize the full force of what Herrick means
when he says:
'TAere is nothing in out experience, there are no mental
powers, no skill in ratiocination or logical analysis, no
capacity to forecast future events, no flights of imaginative
fancy, which do not depend directly or indirectly upon
sensory data^
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WHY WE BEHAVE LIKE HUMAN BEINGS
20
The astronomer figures a bit and announces that the
diameter of Betelgeuse, a star in the constellation Orion, is
200,000,000 miles.
Most of us finished with stars when we learned "Twinkle,
twinkle, little star," "Oh, look at the stars!" or, "Isn't that a
bright star!" We stop our learning of many things when we
can name them. We know many situations and solve many
problems by mere phrases: "Chinese eat rats," "Sweet land
of liberty," "Dirty foreigners," "Liberty enlightening the
world," etc.
By the time we are ready to leave home we have a varied
assortment of facts that we have learned ourselves; they are
part of our own personal experience. This experienced
knowledge is the result of our responses to external stimuli:
stars, rocks, tacks, whistles, pennies, candy, rain, trees, etc.
Some stimuli are received by certain receptors, other
stimuli by other receptors. Qualities especially are learned
from stimuli to several receptors. Thus we learn most things
as hard, soft, wet, dry, smooth, rough, greasy, sticky, etc.,
through no one sense organ. We learn that molasses is sticky
not by looking at it, but by poking our finger in it; sweet,
by tasting it. We know lard because we have seen and felt
and smelled and tasted it, but neither eye nor nose perceives
lard as greasy.
At first we had no organized sense of distance. We walked
into and off" things. The baby falls downstairs until he learns
how far it is to the next step. He learns. He throws a ball
and walks to pick it up; that gives him a sense of distance.
At the creek he "throws a stone across," only the stone does
not cross; he has not learned to distinguish distance on land
and water. By experience he builds up a sense of distance,
space, depth.
An Englishman announces to his Colorado host tliat he
will work up an appetite for breakfast by a walk to "that
408
ACQUIRING HUMAN BEHAVIOR
little hill." He has not learned Colorado atmosphere: the
"hill" is 10,000 feet high, fifteen miles away.
Our two eyes are not far apart; but my left eye can see
what my right cannot unless I move my head. The nearer
the object, the more each eye sees what is beyond reach of the
other; the greater is the resultant eye-strain in binocular
vision. The eye-strain is a clue to distance. As the back-
ground also is seen as two images by the two eyes, another
clue to distance results. The child continually reaches for
objects just beyond reach. As a drunken man does, having
lost much of his learning through temporary derangement
of his "higher faculties."
Our eyes were evolved before print was invented : they are
not naturally adapted for close-ups. In reading or exam-
ining close-up objects, the axis of vision (center of fovea to
center of lens) must change from parallel to an angle.
Countless early adjustments of these axes are part of the
experience which leads to sense of distance.
A silver dollar ten feet away looks different from a dollar
a foot away — its image on the retina is smaller. If I know
the object I see to be a dollar, or a man, or a tree, I have a
clue to the distance of dollar, man, tree. One gets a new
perception of the size of St. Peter's by standing at one end
and watching a tall man walk to the other end. Smaller,
smaller he grows; at last he seems like a child. "It is big!"
we now exclaim.
Distance and depth learning begins with the fact that the
stimulus itself changes with distance from the eyes, and that
every response we make with our eyes requires action in a
complex muscular mechanism. The photographer focuses his
camera. As do I when I lift my eyes from my book to the
clock tower a mile away: I must make far-reaching adjust-
ments in both eyes. They are made by many muscles con-
trolled by several nerves. I may not know I have such
muscles: my body knows. Adjustment of iris alone involves
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WHY WE BEHAVE LIKE HUMAN BEINGS
three distinct sets of muscles that must work in harmony and
at the same time.
We respond to stars by looking at them; to trees by climb-
ing them, by seeing them in sunshine, in fog, in rain, by
moonlight, in summer and winter and spring and autumn.
By and by we know trees.
And hear them also, with two ears. On a dark night we
hear a suspicious sound. We "strain" our ears, turn our
head to the right, to the left: if now one ear does not receive
more stimulus than the other we decide the sound is in front
of us; it may be behind us.
Telephone bell, motor horn, railway whistle, footstep,
mouse gnawing, bumblebee: we knoiv these sounds. By
their intensity we also judge of their distance. But if the
sound is quite new to us, we can not judge its distance by its
intensity.
Wlien a child, I heard a chick in a pasture field crying for
its mother hen; I began to look for it. Every now and then
I would hear it again. For ten minutes I searched, all the
while becoming more mystified. I happened to look up:
high overhead a hawk was circling around. The "chick"
was a haivk! Its cry was so like that of a chick that I had
been completely fooled. But we learn to distinguish many
diverse objects by the sounds they make. We may walk
blindfolded through a street and hear ice, wood, and coal
chopped; wood, ice, stone, and steel sawed; hammering,
filing, the drawing of a rusty nail, jangle of coins and keys,
rattle of dice, rending of silk or paper, scream of a terrified
child, "the car rattling o'er the stony street."
Without eyes, much of the world vanishes; but the blind
man picks up sounds and echoes so far beyond our untrained
ears that we give him credit for "another sense." The
woodman picks up sounds in the forest of no meaning to the
city man, others that fail to reach his ears. But the city man
gets even when the woodman comes to town: he cannot hear
410
ACQUIRING HUMAN BEHAVIOR
himself think, nor knows whether the fire siren is a mile away
or around the corner.
The nose does its bit in our learning of life and things, and
what to leave alone and when the other fellow should take a
bath. We can get used to smells. We can also cultivate our
rather inferior olfactory organ and without eyes or ears come
to distinguish many cheeses, tobaccos, beverages, foods, salt
air and all that pertains to the sea. With nose alone, in
Manchuria, one can distinguish a Japanese from a Russian
railway station. The Japanese are clean.
We learn time by the passing events. We have our own
rhythms for heartbeat, breathing, talking, walking, eating,
etc., all of value in acquiring time sense. The stomach is a
good clock. Where is the sun? Daylight, nighttime. The
banks are closed, the evening paper has come. Or the birds
have tuned up. Or the cocks are crowing. What time is
it: how far have we moved? How long have I been sitting
here: how much work have I done, how hungry am I, how
tired, or how many pipes have I smoked? Time does not
stand still. We learn to move with it.
The body itself is the great learner. General kinesthetic
and special equilibrium organs in our ears give us great
knowledge of the world. Movement in muscles can serve
as stimulus as well as a ray of light in the eye. Before we
learn to dance or play tennis or introduce the speaker of the
evening, we learned to walk on two feet. The knowledge
the body picks up as it walks us through life is a reservoir
of learning from which we draw as from an unlimited bank
credit.
Some of us have no sense, but it is a misshapen, misspent,
and unlearned motor mechanism which has no sense.
Our senses often fail us; our perception is at fault, our
experience incomplete, our judgment wrong, our knowledge
insufficient. But to live is to take a chance. These look like
mushrooms; the cook says they are mushrooms: I take a
chance. Were they mushrooms?
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WHY WE BEHAVE LIKE HUMAN BEINGS
As the diameter of the earth is less than 9,000 miles, I
do not like the idea that the diameter of Betelgeuse is
200,000,000 miles. It makes us small potatoes. I take no
chance. I say: "Bah! How does he know? He has never
been there!" Or perhaps I ask another astronomer. He
says: "No, not two but four hundred million miles!" I
like that less than the other figure. It is "hard to believe."
Which astronomer told the truth? Both, it seems. That
star pulsates like a mighty throbbing heart in a vast universe,
expanding, contracting. It was measured at two different
times, hence the different results obtained for its diameter.
The immediate world that we come to know in our process
of learning to be human also expands and contracts. Of
many things we come to know more; of many things we
thought we knew we come to realize we know next to nothing
at all. But, expanding or contracting, the world we know
is the world in which we live and believe.
21
From a sunlit street I enter a motion-picture theater. It
seems pitch dark. After a few seconds I can see my way to
a vacant seat; a few moments later I can recognize faces
twenty feet away: the theater itself is no lighter than when
I entered. My eyes had become adapted. How?
In sunlight, the pupils of my eyes were contracted to shut
out some of the light-waves. Inside the theater the pupils
began to dilate, thus letting the light-waves fall on the outer
part of my retina, the region of the rods. In these rods is
a substance called rhodopsin (rose-eye), or visual violet. It
decomposes — "bleaches" — under light-waves as short as
320/1,000,000 of a millimeter in length. Light-waves are
forms of energy. Pupil dilation exposed my rods to this
energy. As a result, a photo-chemical change took place in
the rhodopsin: my eyes were "adapted"; I could see.
The human eye is a complex mechanism of the general
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ACQUIRING HUMAN BEHAVIOR
nature of a photographic camera in which certain photo-
sensitive chemicals are excited by varying amounts of light-
wave energy. A chemical reaction takes place. The impulse
of that reaction is carried by the optic nerve into the brain;
if we are not color-blind we "see" red, yellow, blue, etc.,
according to the length of light-waves. But whatever we see,
the fact is that we are of the nature of a mechanism which
is activated by external stimuli. During the reaction, chem-
ical changes take place under conditions which transfer
energy. The changes made, the energy transferred, we are
by that amount and to that extent changed. Each change is
registered somewhere within us, and to that extent influences
all subsequent reactions.
Those who lived through the Iroquois Theater fire cannot
forget it. It is buried into their reaction-system and influ-
ences their behavior. During those few moments the
dynamic nature of their reaction complex received impulses
that changed the quality and quantity of its sensitivity. To
thousands the name Iroquois is a cause of excitation, an
energy-laden stimulus calling out avoiding reactions. The
theater was renamed.
I am now in my seat in what was once the Iroquois
Theater. I note the exits more attentively than usual, decide
which is mine should "anything happen." That stimulus is
so strong and memories so crowd my mind that I am hardly
conscious of the preliminary music; it arouses no activity
in the cortex of my brain. My revery ends when the music
changes. My senses now become alert. I begin to focus my
attention on the picture I am about to see, the picture that
diverted me from my routine work and impelled me from
the sunlit street into the darkened theater.
Meanwhile, certain cortical centers of my brain have
become the dominant centers of activity. They are now con-
suming energy at a rapid rate; the arteries leading to the
brain have expanded to supply the demand for more
oxygen; muscles controlling the bellows which work my
413
WHY WE BEHAVE LIKE HUMAN BEINGS
lungs have been stimulated to permit of the rapid elimination
of the carbon dioxide of oxygen combustion and the rapid
restoration of the supply of oxygen. Before the first scene
is flashed on the screen, impulses of a hundred natures have
been dispatched from brain centers and responses made
throughout the entire bodily mechanism. And as scene after
scene of "The Birth of a Nation" is unwound, new impulses
are hurried along.
By the time the picture is finished, I have fled in terror;
I have committed murder; I have fallen in love at least twice:
all within two hours. No part of my body has been quiet,
unaff"ected, unchanged. Few, if any, of my muscles but have
joined in; few. if any, of my glands have lain dormant. Cen-
ters of activity have shifted — as one flees or fights, leads
an army to victory or falls in defeat, or must remain in one's
seat while lovely Mae Marsh is driven to her death by a
madman.
The least active organ in my body was the digestive.
Digestion is a complicated process requiring much energy;
my energy was exhausted elsewhere — I had none to spare
for alimentary canal. All I asked of it was sugar from the
liver: sugar feeds the fires of hate and fear and love, and
brainstorms.
In those brainstorms — and there are many in "The Birth
of a Nation" — millions and millions of neurons listened in,
gave decisions, issued orders; correlating, coordinating,
adjusting the body, preparing it to fight, to murder, to mate.
The body responded. Each bit of bodily machinery could
respond because it was accustomed to respond to messages
carried by the nerves of the body. The body grew up with
the nerves. What the nerves know, the body knows: the
nerves integrate the body and enable it to function as an
individual.
And yet, with all the excitement and needs of blood to
brain and to the fighting-fleeing mechanism, the long intestine
kept its rhythm, the fine cilia lining air-pipes kept moving
414
ACQUIRING HUMAN BEHAVIOR
like fields of grain, the glottis never forgot to execute its
complicated movements, however, hard I swallowed. Even
my empty stomach kept its place: it did not growl or make
hunger-contraction gestures.
It is the entire body that responds, the entire body that
learns, the entire body that grows up. It was the entire body
that recalled with bated breath the Iroquois fire, noted the
exits, disregarded the music, and, spellbound, saw "The Birth
of a Nation."
All living beings are excitable and must make adjustments;
man most of all. Other animals come in contact with as
many points of the outside world as man, but none can so
vary its responses, because it has no such storehouse in which
to store responses already made, nor so many words with
which to answer back; none must respond to such diverse,
complex, and rapidly changing situations.
On one side of me was a Negro ; on the other, a Virginian ;
in front, a maid; behind, a youth. What was "The Birth
of a Nation" to their minds' eyes?
415
CHAPTER VII
FROM THE STANDPOINT OF THE NEWER PSYCHOLOGY
1. Instinctive Activities. 2. The Hunger Complex. 3. The Complex Appetite.
4. The Sex Complex. 5. Love's Coming-of-age. 6. Bisexual Behavior.
7. Conditioning the Sex Complex. 8. Marriage Behavior. 9. Freud's Devil and
Other Psychoses. 10. Fake Psychology. 11. Reading the Mind. 12. Measuring
Intelligence. 13. Character and Personality. 14. The Ideal in Human Be-
havior. 15. Socially Useful Behavior. 16. The Goal of Creative Evolution.
1
Any attempt to explain or to describe man by a set of
rules or by a special formula, or as cast in a given mold, is
predestined to failure. Man is a something happening all
the time, a going concern; he makes his rules, revises his
formulae, and recasts his mold in the act of being and while
going. It is in man's nature that he does not stay put.
Human behavior is individual behavior; it is the indi-
vidual that grows up, that functions as a living being, that
behaves as a more or less human being. Genetic history,
visceral processes, and somatic behavior are only phases or
aspects of the same behaving individual. To restrict our
interest to any one of these phases is to let us into human
morphology, human physiology, or human psychology, but
not into the whole nature of man.
The blind men fussing around an elephant came to some
interesting conclusions: the leg was like a tree, the tail like
a rope, the trunk like a snake, the ear like a fan; but tree,
rope, snake, and fan added up gave no real understanding
of elephant. Nor does a lifetime spent in studying oxygen
416
FROM THE STANDPOINT OF THE NEWER PSYCHOLOGY
and hydrogen prepare us for understanding water; but a
knowledge of water helps us understand living things, includ-
ing vital processes in living beings and cultural traits in
human behavior. In other words, psychology must take a
very deep breath if it is to obtain a very broad view of human
behavior. It must go to the bottom of life to discover how
life behaves at the top.
And yet psychologists and sociologists continue to attempt
to force human behavior into specific desires, wishes, traits,
impulses, functions, instincts, what-nots, rather than study it
in terms of specific protoplasms which have had a history
and learned their lesson. It will be instructive to look at
one of these attempts.
I select McDougall's list of "instinctive activities" not
because it is the worst psychology, but because it is bad
enough to illustrate what happens to a psychologist when he
cuts himself loose from biology.
Instinctive behavior is blown-in-the-bottle behavior; and of
that kind of predestined, foreordained behavior man has less
than any other animal. Man's really distinguishing trait is
his capacity for modifiable behavior. Without that capacity
he is a moron ape, and not too clever at that; with it he is
man, ruler of the earth, creator of human culture and so-
called civilization.
Instinctive behavior is the crowning glory of bugs and
insects; we cannot compete with them in that kind of
behavior — ^just as we cannot compete with the earthworm's
capacity to grow a new head to a tail and a new tail to a head
when its body is cut in two. Ours is a higher nature.
Look at a silkworm. It emerges from the cocoon and lives
a simple life of from ten to twenty days without a meal, but
with a mate. The female deposits her 500 eggs in a single
layer in a definite pattern, on a mulberry leaf or something
just as good for her caterpillars to eat. She has tdi do it,
she cannot help herself. Miss McCracken's experiments,
reported by Herrick, show us why.
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WHY WE BEHAVE LIKE HUMAN BEINGS
The silkworm has a brain and five pairs of ganglia or knots
of neurons, one pair in the neck, four in the abdomen. Snip
off her head: the headless body lives out its allotted days
and does not seem to mind the operation. The headless body
can also be induced to mate and lay the normal number of
eggs in the normal way; but the headless body can not dis-
tinguish a mulberry leaf from blotting paper.
Cut the neck off also — the legs go with it : she cannot mate,
but she can live; and if already mated, she can lay her eggs
but not arrange them, because she has no legs; but her
abdomen tries to arrange them by twisting around while the
eggs are being laid. Cut the first, second, and third abdomi-
nal ganglia: she still lays her eggs.
Which means: the head is necessary for choosing a leaf
and a mate; but not for living or for mating or for laying
eggs. The brain sets off certain instinctive activities involv-
ing discrimination; but activities of the body segments, once
initiated, carry on without the brain. Only when the last
ganglion of the abdomen is cut is the egg-laying reflex
abolished.
Instinctive activities, functioning on inherited reflex arcs
of nervous structure : predetermined behavior, instincts. The
moth must fly into the flame — its reflex in response to light
impels it; it could keep away from the flame only with a
surgical operation on its phototrophic mechanism.
Instinctive behavior is insect behavior at its highest;
human behavior, modifiable behavior at its highest. Even
birds have a picturesque repertoire of instinctive behavior,
but the headless body of a bird does not live, let alone mate
and lay eggs.
Now look at McDougall's list of our instinctive activities —
with the "names of accompanying emotional qualities" in
parenthesis :
Escape (fear) ; combat (anger) ; repulsion (disgust) ;
parental (tender emotion) ; appeal (distress) ; pairing
(lust) ; curiosity (curiosity) ; submission (feeling of subjec-
418
FROM THE STANDPOINT OF THE NEWER PSYCHOLOGY
tion) ; assertion (elation) ; social (feeling of loneliness) ;
food-seeking (appetite) ; acquisition (feeling of ownership) ;
construction (feeling of creativeness) ; laughter (amuse-
ment).
There is a bird in Australia called the Laughing jackass.
There is nothing in McDougall's list that that bird is not
impelled to do at one time or another. But whether it is
social because it feels lonely, pairs because it is lustful,
laughs because it is amused, is elated when it asserts itself,
or appeals because it feels distressed, I have no means of
knowing.
Submission is not "instinctive" action in man, worm, or
primordial protoplasm. Some of us know when we are
licked and when it pays to throw up the sponge and cry
Kamarad. And some unfortunates with defective glands, or
whose "instinct" of assertion has early in life been kicked
or beaten out of them, probably do have "feelings of sub-
jection." Uriah Heep was so 'umble he cashed in on it for a
while. But submission is no more instinctive in man than
it is in wild cats.
Much is made of the "instinct to hoard, with its feeling
of ownership, of possession." Some hang civilization on it.
True, many are so in the habit of acquiring that hoarding
seems as instinctive with them as it is with bees to hoard
honey or with squirrels to hoard nuts. But acquisition of
what? What is it that man instinctively hoards? Surely not
capital; if so, it is a poor instinct these days. Only about
four out of every hundred have hoarded enough to live on.
The average Hindu has hoarded just one meal; that is all
there is between him and starvation.
Pick up your toys! — ^how many times does every mother
say that. The instinct of man- and monkey-child is the
same : reach for it, taste it, smell it, thump it, throw it away.
But try to take it away — or a bone from a dog! There is a
fighting instinct. One of the curiosities of civilization is the
things people fight for. Boys fight for marbles; no mother
419
WHY WE BEHAVE LIKE HUMAN BEINGS
has to beg her son to hoard them. Born with an instinct for
life, at six marbles have come to have life-giving value.
Construction? Destruction, rather. If we cannot eat it,
we pull it to pieces. Sometimes this tendency to examine and
destroy gets so overlaid with distorted habits as to result in
sadism.
We are born with certain instinctive activities and emo-
tional capacities; the so-called human instincts above cited
inhere in living beings. What seem clear-cut instinctive
actions are learned or habit reactions based or built on some
innate emotional response or on attack and defense reactions
as old as life itself. And any attempt to describe human
behavior in terms of such instincts is to try to catch birds
by salting their tails; worse, it is to fail to understand the
fundamentals of animal evolution.
2
How does the baby know it is hungry? It does know: and
if born of an undernourished mother, has been hungry for
days and enters the world grub-struck.
We speak of drives, impulses, wishes, instincts, reflexes;
but living beings must eat or they die. Hunger is back of
life, the primordial drive in life. And if life waited for the
doctors to decide whether hunger is physiology or psychology,
life would starve to death.
The fact that an infant enters the world grub-struck may
be the most momentous single factor in a lifetime of behavior.
The way the appetite back of that hunger complex becomes
conditioned may be the decisive factor in shaping that indi-
vidual's career. Without hunger and its attendant appetite
there could be no genetic, visceral, or somatic behavior.
Even psychics are believed to be subject to hunger.
Hunger has led to crime, to suicide, and to cannibalism;
and the fear of it, to war. It can make us feel faint, give us
dull headaches and gnawing pangs — tliough we are not
420
FROM THE STANDPOINT OF THE NEWER PSYCHOLOGY
always certain whether the pangs gnaw in the head or in the
stomach, or whether it is the mouth that feels hungry. But
we can get so hungry that the sight of food makes us "sick,"
or "too dog tired" to eat. But why a fast can make one man
cantankerous and fit another for a spiritual life is as yet a
fair puzzler. What is certain is that if the way to a man's
heart is through his stomach, the stomach is worth looking
into.
It has been during the last fifteen years, and more learned
of its nature than in 5,000 years' wondering about it. By
cutting nerves, inserting balloons, and X-ray observations,
Cannon cleared up much that was obscure. Carlson let in
more light, chiefly by experimenting on a Czech who feeds
himself through a tube in the wall of his abdomen because
an accidental dose of strong caustic soda closed his esophagus
years ago.
The hunger mechanism is in the muscular walls of the
stomach. The stomach itself announces that it is hungry by
violent rhythmical contractions lasting half a minute, alter-
nating with mild normal or tonus rhythms of twenty seconds'
duration. These alternating rhythms continue for from
fifteen to twenty minutes. If this call for food is unanswered,
the stomach gives up and remains quiet for from one to three
hours. Then repeats the call.
That mechanism and an empty stomach come with every
normal baby. With one big difference between baby and
adult: the time between unanswered calls is not hours, but
minutes. The adult has already built his body and can live
on his fat; the baby has to build its body. Besides, the baby's
skin area in proportion to body volume is larger than the
adult's; it loses heat faster, hence needs more fuel for its
furnace. And as soon as it becomes active, it is very active.
No action without energy. If the infant has to keep yelling
for every meal, still more food is required: even an infant's
stomach cannot signal "more fuel" without burning up some
that would be used otherwise for growth or exploration.
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WHY WE BEHAVE LIKE HUMAN BEINGS
An adult's stomach signals hunger from four to six hours
after a full meal; the baby's, within three hours — rarely more
than three and a half or less than two and one-third hours.
Thus nature answers a question often put to the doctor: when
and how much? As much as its stomach will hold and as
often as it cries for more. Colts, calves, and kittens grow
up that way and seem to do well.
We feel hungry when, and in normal life only when, the
empty stomach begins its hunger-contractions. The more
violent these contractions, the hungrier we feel: it becomes
"painful." Mild hunger is sensed less as pain and more as
a general kinesthetic sensation.
We have no specialized receptors for the many sensations
by which we are aware of our bodily states and emotions.
But the entire body-within-the-skin is sensitive to pressure.
Strong pressure anywhere on the body is felt within: hence
pressure receptors, or muscle or kinesthetic sense. There is
no special receptor for intestinal cramps, but we can feel
them. There is no known receptor for hunger pains, but
we never sense them as we do cramp pains in skeletal muscles.
Colic pains in the intestine do not make us feel hungry.
The empty stomach contracts. Its contractions are
stimuli. The reaction to such stimuli is completed with food.
What happens in the meanwhile : what goes with hunger, what
are the accessory phenomena? The animal gets more
excited: beasts, babies, and men. Hungry protoplasm is
more irritable than a just-fed man or baby: it can think of
nothing else. Even the human cortex at such times has been
known to get so crossed that only a divorce court could
untangle the lines.
Also. The heartbeat rises from eight to even thirty per
minute. Blood pressure rises. Salivary glands more active.
All of which leads to feelings — emptiness, faintness, rest-
lessness, drowsiness, headache, even nausea. It all depends
on the individual: intensity of stomach contractions, condition
422
FROM THE STANDPOINT OF THE NEWER PSYCHOLOGY
of stomach's sensory nerves, especially the nervous organiza-
tion or control.
Suppose the hungry baby is not fed, that the reaction begun
with hunger-contraction stimulus is never completed? Death,
of course. Meanwhile it lives off its own body, suffering
much at first, then less and less. Carlson starved himself for
five days. He lost eight pounds. The hunger contractions
increased in intensity. The sensation of hunger was strong
ten hours after his last meal and continued strong for three
days. Food looked good throughout the five days, but on
fourth and fifth days he could forget food. He felt some
mental depression the last two days, also loss of physical
strength. But never during the fast was his discomfort so
great that it could be called pain or suffering, nor did it inter-
fere with his work. Mental recovery from the fast came with
the first meal; recovery from physical weakness, after the
second day. He then felt as if he had had "a month's vaca-
tion in the mountains." He thinks an occasional fast for a
healthy adult "may add to the joy of living and to the length
of life."
In a Carnegie laboratory a man weighing 134 pounds
began a test fast. With no food, but plenty of distilled water,
he lost 28 pounds in a month. He lost some muscular
strength, but gained in sharpness of senses and ability to
learn new tricks.
The first three days of a fast are the hardest. Suffering
thereafter is imaginary, due to fear or panic. "Voluntary
starvation is in no sense a heroic act" ; the "exalted" feelings,
sights, and sounds reported by fasting ascetics are pure hal-
lucination, thinks Carlson. Their brains are not more active,
but less: they dream! Starvation changes the nature of the
blood and the tissue of the brain. Hallucinations are children
of the emotions rather than of the brain.
If the baby does not like its first meal, it will refuse it,
as a chick does a bitter worm. Man is born with sucking
reflex and hunger mechanism; his appetite begins to be con-
423
WHY WE BEHAVE LIKE HUMAN BEINGS
ditioned with his first meal. We do not inherit a thirst for
milk or beer, or a craving for pickles or alcohol.
All eat to live and some live to eat. We inherit a hunger
complex; we acquire a complex appetite. Both hunger and
appetite furnish their quota to prisons, but succeed fairly well
in keeping out of the insane asylum. Hunger fills alms-
houses, appetite supplies hospitals. The complex appetite
has become an important factor in human culture and has
even "shaped the destinies" of some nations. For details,
consult an historical index under "Nutmegs," "Spice
Islands," "Opium Wars," etc.
3
He is a "born hog." He may deserve the epithet, but there
are no Suince in man's ancestors. Human hogs are made, not
born. Greed is not part of our inheritance, nor to the stuff
we are made of has it biologic value.
Food has biologic value. We are born with a hunger com-
plex and of parents who know by our behavior when that
complex begins to act. Their reaction brings us in contact
with food. That contact — physical and chemical — releases
the sucking reflex, which continues until the stomach signals
"Stop." The hunger complex satisfied, we are not hungry.
The hunger mechanism retires and the infant can give its
mind to other matters. Or, as we say, we can now get down
to business!
That "business" may be "big," but it ends with, Wliere
shall we eat? Later, What shall we eat? These questions
are big business to millions of people — among the important
"problems of life."
How are they solved? In relation to the hunger complex
and the body's requirements? Or in reference to a complex
appetite which ranges from soup to nuts and includes corned
beef and cabbage on Monday, fish on Friday, brown bread
424
FROM THE STANDPOINT OF THE NEWER PSYCHOLOGY
and beans on Saturday, and a gorge on Sundays, holidays,
weddings, and wakes?
The hunger complex is a biologic necessity and begins
with a mechanism of special receptors in mouth and nose
by which we distinguish noxious physical and chemical
stimuli. We may turn up our nose at many things, but cer-
tain things make us hold our nose. The bacteria of decay are
enormously important in the nitrogen cycle, but we prefer
our ammonia in smelling-salts. Nor is it without biological
significance that our taster for bitter is thousands of times
more acute than for sweet.
We get "hungry for" this or that. What is back of that
particular hunger? What is it that makes our mouth water?
The newborn has never tasted food, good or bad: how does it
know that it tastes good or bad. It must learn. It does
learn; by the same process that life itself learns — by trying.
Before many months the infant has tried out everything it
can get its hands on. Its limit is the vigilance of parents
and reachable environment. Whether maternal love is an
instinct or not may be left to the doctors to decide, but there
is no escaping the biological fact that prolonged infancy is
possible only with parental oversight.
We had the benefit of mother's taster. When the pie was
no good she gave it to the tramp. The mother tries it out —
whether it be the four-handed mother in the forest or the two-
handed mother of men. Trial and error carries the infant
far; and he may prefer the blacking on father's boots to the
blacking mother uses on the stove. But the food the child
memorizes is the food mother makes. If the first meal tasted
and smelled good, and if the pleasure of a full stomach fol-
lowed the pangs of a gnawing stomach, the infant has learned
a lesson.
Repeat eight times a day for months; and three times a day
for years. "Like mother used to make" is good psychology
because it is sound biology.
The first meal was the answer to the hunger complex. The
425
WHY WE BEHAVE LIKE HUMAN BEINGS
"set" of that meal was the conditioning factor in the next one:
did it "taste like more"? If it did, the foundation was laid
for an appetite for that kind of food. By and by the child
is weaned: other appetites are built in by the same tastes-
like-more process.
So we come to like this and that, and this and that kind of
cooking, surroundings, etc. But back of appetite is always
an experienced or learned process: did it look, smell, and
taste good, and did it "set" well. If so, we like it; we eat
it with a relish, the memories of it make our mouth water;
in front of it, these memories are real stimuli to the nerves
of our mouth and nose. They are keyed up to such stimuli.
We may not be hungry, yet the mere sight of caviare may
touch our appetite off. The urge is not for food, it is an
appetite for caviare. This appetite differs from hunger. It
also has a different quality from most other pleasant sensa-
tions. As Carlson says: "the fragrance of the rose in the
garden may be as pleasing as the fragrance of the roast in
the kitchen, but the desire to smell the rose cannot be com-
pared with the urge to eat the roast."
The appetite complex begins with memories. What is it
that remembers? Cortex, yes; but the feeling is in the throat
and mouth and nose, combined into a kinesthetic sensation in
that particular region. The increased salivation and the
heightened tonicity of the nerves of taste, odor, and of pres-
sure, help to make the appetite complex.
On a hot day we may sigh for a drink of water "from the
old spring," but when we have a taste for any particular
water it is for something in the water: pure water has no taste,
nor odor. Beer has both; an appetite for beer is appetite for
beer. One may desire beer without being thirsty; or fudge
without being hungry.
Sitting down at the table does not shut down hunger con-
tractions; eating does. With our first mouthful, gastric juice
begins to be secreted — the contractions stop. But we must be
eating food: chewing a stick, even of tobacco, does not start
426
FROM THE STANDPOINT OF THE NEWER PSYCHOLOGY
gastric juice any more than the sight or smell of food does.
Chewing meat is good to stop a stomach gnawing. A pie or a
pudding or a fruit is even better: that is why they end the
meal.
We all eat our "peck of dirt." How about dirt-eaters?
There are, especially children with abnormal appetites for
clay, chalk, lead pencil, etc. Children experiment; if no
harm comes and they like the taste, they keep it up. Same
way with pickles, mustard, pepper, gum, licorice, tobacco.
Whether an appetite is "depraved" or merely abnormal de-
pends largely on taste, and taste depends on habit, custom,
social usage. Caterpillars, snakes, dogs, overripe cheese,
sharks' fins, "gamy" game, snails, frogs, toads, lizards,
monkeys, grasshoppers, grubs, dogfish, brains, tripe, birds'
nests, devilfish, blood: all favorite dishes — somewhere, some
time. Each man to his own. Tastes are not to be disputed,
nor appetites questioned.
Man must eat: it is his nature. When, where, what, de-
pend on his nurture. Hunger is the best sauce. And the
best hunger-producer is chopping wood. After that come all
other forms of physical work. The body we inherit was
built up by work, its functioning apparatus is arranged for
work. When we do not work our body must make other
arrangements. Civilization furnishes these in the form of
"Institutions." They are a credit to civilization. We shall re-
quire more, for we are only at the beginning of "Progress."
4
There comes a day when the gates to the elephant house are
shut — must; as Mr. Freud would say, he has a libido complex.
It is also called the sex urge. The elephant is dangerous. The
urge is so strong that bananas and peanuts do not inhibit it.
Sometimes nothing can: he gets so mad he must be shot.
There comes a time when the farmer misses the sow's face
at the trough. If he knows the livestock of his neighbors, he
427
WHY WE BEHAVE LIKE HUMAN BEINGS
knows where to find her. It may be miles away and many
fences in between. She will be there.
Laboratory tests have been made to determine the danger
a hungry animal will face to get food. One easily measured
is the crossing of an electrically stimulated plate: it must
accept the shock to get at the food. No shock short of elec-
trocution will stop the food-hungry rat. It will face the same
charge for a mate.
Biologically, rape and the theft of a loaf of bread are
natural behavior; celibacy and asceticism are crimes against
nature.
The biologic function of sex is reproduction. In all species
with sexual reproduction, the sex impulse is and must in-
herently be as strong as the impulse to live. The mechanism
for reproduction is enormously varied, but not more so than
other mechanisms useful for food and oxygen metabolism,
for capturing food, for defense from enemies. The mating
cycle also varies with different species, as does the period of
infancy, the relationship between parents and offspring, and
the methods of courtship.
In short, each species has its own reproduction complex. So
far as the species is concerned, the individual male or female
which does not play his or her part in this complex con-
tributes nothing biologically useful to the species and might
as well never have been born.
Sterility in vertebrates is not more unknown than other
congenital variations which distinguish defective individuals
from the normal run. In states of nature it is to be presumed
that all normal individuals play their part in the reproduction
complex. Why this is so is no more, no less, explicable than
why a food complex impels animals to seek and ingest food.
The drive for food is backed by a sensori-motor mechanism
which functions until food is secured and ingested. Food
itself in the alimentary canal is stimulus or drive for further
actions and reactions. But the initial drive was hunger: it
428
FROM THE STANDPOINT OF THE NEWER PSYCHOLOGY
was a potent impulse to reactions, thereby bringing about
adjustment.
The drive for a mate, likewise, is backed by a sensori-motor
mechanism which functions until the mate is secured and the
sexual act completed. Subsequent changes are themselves
the stimuli which impel to nest-building and other activities
which will be useful for the life of the progeny.
Biologically, the chief distinction between the food-hunger
and the sex-hunger impulses is that they function in different
rhythms. These vary in different species, even in the same
order of vertebrates. But in general the food rhythm is
fairly continuous from day to day throughout life; the sex
rhythm is confined to certain fairly definite years of the in-
dividual life cycle, and within these years to fairly definite
seasons or periods.
A hardly less important biologic distinction between the
food-impulse and the mate-impulse is that in one case the
adjusting reaction is primarily individual action; in the other,
two individuals of opposite sex participate — and only if they
agree to such participation. Herein is an element of huge
import in setting patterns of behavior, even in modifying
structure.
Species vary greatly in these two respects. In some,
secondary sexual differences are slight ; in others, marked and
highly characteristic — as in most species of birds, many
species of vertebrates, and the anthropoid apes. Patterns of
behavior vary, from extraordinarily complex courtship proc-
esses in some birds to next to no courtship in many verte-
brates. But whether the courtship be simple or complex, short
or prolonged, there must be the biologic equivalent of court-
ship in all species with sexual reproduction.
There are three biologically significant facts:
( 1 ) The mate-impulse is driven by an unconscious mecha-
nism and not by any "desire of offspring." Whole species of
animals mate and never survive the mere depositing of the
eggs. The primary impulse is not eggs, nests, or cradles:
429
WHY WE BEHAVE LIKE HUMAN BEINGS
it is for a mate. As in food; animals do not seek food for
"processes of metabolism," they seek and ingest food because
impelled by food-hunger. That hunger satisfied, the alimen-
tary canal will do the rest and furnish the voiding stimuli.
So with the mate-impulse. It knows nothing of cubs, squabs,
or children. The drive is for the mate.
(2) The mere fact that this or that species reproduces
through the mechanism of sex means that the two sexes must
be different and must be responsive one to the other. In other
words, in sexual reproduction there must be two types of
bodily structure, two modes of behavior. Five tomcats in a
row on a fence: the appearance of a tabby may be quite as
great a stimulus for action as a dog or a rat.
(3) Sterile individuals among vertebrates are abnormal;
sexually mature but unmated individuals are deficient either
in inherent mate-hunger or mate-attractiveness; neither group
has biologic value. The food-hunger impulse must be strong
enough or the individual dies; the mate-hunger must be strong
enough or the species dies. The species only lives through
its individuals. The individual mate-hunger must lead to
action or there is no adjustment.
In human organization sex plays its part as a determiner
of certain characteristic forms of behavior. But normal in-
herent modes of sex behavior, no less than other inherent
modes of response for adjustment useful for the species, are
subject to learning: the whole sex-complex becomes condi-
tioned. Individual sex behavior is only to be understood in
the light of individual inheritance of mate-hunger mechanism
and the learned modes of response for adjusting the impulse
of that mechanism.
There are always: the individual; the situation. Both are
complex in human society because the individual is capable
of such varied responses and because society assumes the
right to condition the responses. In every phase of bisexual
behavior, certain unvarying biologic factors and special vary-
ing social factors combined make up the definition of the
430
FROM THE STANDPOINT OF THE NEWER PSYCHOLOGY
situation. But back of the sex-complex is a fact-complex
which must not be mislaid :
(1) In bisexual reproduction the function of the male
element is to release and set moving the energy stored in the
ovum. It is the single ovum that is fertilized: thousands
of male cells compete among themselves for the honor. The
female is the older and more important of the two sexes.
(2) The ovum fertilized, the male is free: to roam or to
die; reproduction thereafter being dependent upon the con-
tinued existence of the female until the ovum is incubated.
This process requires 280 days of a woman's time. The
mother is always present at delivery.
(3) After delivery, the woman also is free: to roam or
to die. The offspring need never know father: many do not;
nor mother: some do not. The offspring wants food. If the
hand that feeds it is a black mammy's and the food is from a
bottle and all agreeable, the offspring will learn to love the
black mammy and the glass bottle: and, like the lamb, will
follow her to school or any other place the bottle goes.
Of course, children "love" their parents; and will honor
and obey them if "honor" and "obey" are conditioned into
their response repertoire. The "instinct" is not confined to
man. Life itself must eat, and learns to love the hand that
feeds it.
Parents "wake up" to the realization that their children do
not "love them any more." Exercising their "rights" as par-
ents, they "demand" love, and call their children "unnatural"
if they do not respond. A normal child learns to love any-
thing or anybody associated with its love experience. The
child does not love its parents because they are parents, but
because they are lovable.
5
When a woman says: "I hate that man!" what does she
hate him with? Does hate spring from rage impulse which
drives us to anger when restrained, or is it the opposite, the
431
WHY WE BEHAVE LIKE HUMAN BEINGS
detumescence of love? Suppose she says: "I hate lavender"
— women do say such things. I heard one say: "I hate Paris."
Most women "love" Paris, some "simply adore" it.
I love corned beef and cabbage. Sight or odor of corned
beef and cabbage makes my mouth water. My mouth waters
only when I am stimulated by something within my food-
hunger repertoire. My mouth-water mechanism is made up
of glands, muscles, nerves. An adequate stimulus sets it
off. Call that activity tumescence (swelling). And note
that I may leave the restaurant with a full stomach, and yet
the odor of broiled mushrooms as I pass out the door sets my
mouth watering again.
I sit down and order broiled mushrooms. The first one I
spear has a hair on it. I try again : and encounter a dead fly.
These are not pleasant things, but such make or break appe-
tites. I have lost mine for broiled mushrooms, possibly for-
ever. The very thought of mushrooms makes me sick: no
mouth-water, no "good feeling" in the food-appetite mecha-
nism. Call that detumescence.
The sex-appetite mechanism is much more complicated;
has more parts, more nerves, is capable of more devastating
sensations. Call it the erogenous (love-producing) zone.
This zone is all in order at birth. By conditioning processes
it learns to respond to widely differing stimuli by the time the
mature puberty glands begin to send their impulses to satisfy
what by now is a definite and specific mate-hunger.
Which means that by the time we reach the marrying age
the mate we choose, if any, will be more or less already
picked out for us. Romeo-and-Juliet is sound psychology and
natural behavior. "That is the man I want." "I couldn't
possibly love that woman." We are so certain we call it
instinct; and say that "marriages are made in heaven."
Maybe. But it is on earth we wake up to discover that we
have married a dimple, a Cupid's bow, a broad chest, a
mustache, purple socks, a Roman nose, a blue dress, a trim
ankle, or a head of hair. That, in short, we have married
432
FROM THE STANDPOINT OF THE NEWER PSYCHOLOGY
certain trimmings and accessories. And we go on through
life buying magazines by their covers, cars by their colors,
and coats by their buttons.
"Things and places," says Watson, "tend to become asso-
ciated with organic responses, specifically those with love."
Every object, by virtue of the original bent of the individual,
or through conditioned reflex or habit, calls out overt or de-
layed response in the motor mechanism; also, "a definite and
complex group of reflex activity in the erogenous zone."
Excitation in this zone arouses two fundamental kinds of
impulses:
(1) Tumescence: rhythmical contraction of certain mus-
cular tissue and increased secretions. "If functioning alone,
the impulse will lead to positive seeking movements and
ultimately to the unfolding of the instinctive reproductive
mechanism."
(2) Detumescence : inhibition, and relaxation of other
muscular tissue and inhibition of secretions. "These im-
pulses at the motor center, if not inhibited, would release
avoidance movements."
Here, then, is the sex-appetite mechanism which early in
life begins to sort the little world about into loved ones and
those it does not care for. Through the mechanism of habit
and conditioned reflex functions, objects which at first had no
emotional value "come later to arouse faintly or overtly one
or other of the two impulses" — tumescence or detumescence.
To the objection that this view over-emphasizes the in-
stinctive factor of love, Watson points out that the love and
do-not-love factors are at the bottom of home, general, social,
and vocational life. We work long hours to improve our
position to make more money to carry on home life on a
broader scale. "The activities centered about loved ones
from infancy to old age are easily the most important factors
in life. No wonder that our acts are connected with and
evalued by the connections lying below our language level."
Here again, as always, we come back to that as yet unsolved
433
WHY WE BEHAVE LIKE HUMAN BEINGS
problem of two faces: the significance and extent of individual
inheritance; the degree to which this individual inheritance
can be conditioned. Do our original tendencies make us, or
our parents and our teachers and our environment? Or, put
the question this way, Where does nature leave off and nurture
begin? Nature never leaves off — we may be certain of that.
Nurture begins at once — ^there is no doubt about that. But,
as Watson says, as long as v/e keep up our sentimental drivel
about children instead of looking at childhood as a problem,
the problem of individual bents and capacities will remain as
chaotic as it is now.
As it is now, we are all tied up with sticky sentimentality
about Alma Maters and hurrahing without stopping to in-
quire if it is worth hurrahing about. We have a huge youth-
cult; enormous and costly equipment to train boys and girls
in the way they want or are fitted to go? No; "in the way they
ought to go!" As one calls the roll of the men who have ren-
dered useful social service, one is impressed by the notion
that most of them succeeded not because, but in spite, of their
"training." It almost seems as if the best equipment with
which to start life is a widowed mother who turns one adrift
at eight.
Born with an elaborate mechanism for adjustment, we face
three doctors, two nurses, several servants, father, mother,
aunts, uncles, etc., all on their toes to adjust for us. Nature
never gets a chance. Nurture cries when we do not smile
back. To make us smile, they tickle us under the chin and
trot us on their knees and bribe us with candy and ribbons
and gewgaws.
And so our food-appetites, sex-appetites, fears, and rages
slop over into endless things that are not to be eaten or loved,
nor to be run from or killed. Indigestion — or adiposity;
celibacy — or promiscuity; afraid of shadows, facts, and
death; and war on our neighbors instead of against poverty,
squalor, and ignorance.
Love and such move the world, move it in many ways be-
434
FROM THE STANDPOINT OF THE NEWER PSYCHOLOGY
cause instinctive responses can be and must be conditioned.
The conditioned response is our only mechanism for learning
to behave like human beings. Love is a driving force of
great dynamic power. But such grist as it does grind!
6
The newborn is a loaded stimulus for parents and com-
munity. The nature of the load it brings will vary with the
sex of the child. The girl may be as welcome as the boy.
But the fact of girl or of boy colors the environment for the
developing child.
Suppose there are twins, a boy and a girl. Each may seem
to face the same situation day after day. But, as society is
constituted, each faces a different situation. The sister makes
certain appeals because she is a female; the boy, because he
is a male. Certain modes of behavior are expected because
"You are a boy''; quite different responses are expected be-
cause "You are a gir/." As a consequence, before they have
a verbalized behavior they have acquired the manual and
emotional habits expected of boys and girls. The girl has
no inherent impulse to play dolls and mud pies, or to wear
curls, ribbons, dresses, shoes, necklaces, earrings ; nor has the
boy for drums and other noise-making machinery, or for
short hair and pants.
The girl is molded to make "womanly" responses; the boy,
to behave like a "little man." Boys are conditioned to face
one world; girls, to face another. The two sexes do not see
alike because their eyes have not learned to look at the same
things alike; for each sex, the glasses have a different color,
focus, and range.
Men do not "understand women." How can they? But the
reason is not because women's nature is fundamentally dif-
ferent from men's; rather that ten or twenty or fifty years of
having to live "like a woman" go into her make-up.
Freedom of movement is soon limited for girls. Some
435
WHY WE BEHAVE LIKE HUMAN BEINGS
learn to skip the rope and play jackstones only under pa-
rental frowns. And as for climbing trees, playing marbles,
going off swimming, "Who ever heard of such a thing!"
Shades of limited freedom for girls depend on families,
communities, rank, class, etc. But in the background is al-
ways a general limit in movement, emotions, and language,
beyond which the girl is not supposed to go. "Proper
spheres," "womanly ways," "unmaidenly manners," etc.
The boy of six has a much wider field of exploration than
his sister, especially if sister is "handy about the house." By
ten, his freedom is greater yet. He can stamp around and
shout and whistle and scrap and "talk back" in ways denied
to his sister.
Because they must learn "nice ways," girls have less oppor-
tunity to learn certain specific motor habits and in general
less occasion to develop their skeletal muscles. She cannot
throw a ball when she is fourteen: she did not begin to throw
stones at the age of three. Rules of habit formation and
limits of dexterity are not inherent in each sex. How many
boys of twenty could run a hundred yards in ten seconds flat
if they had worn dresses and such accessories all their life?
If it is "unwomanly" for girls to throw stones and run
races, it will be "unnatural" for them later to be expected to
compete with men on equal terms.
A boy brought up on "Don't be a sissy" will have a be-
havior different from that of a sister for whom being a sissy
is normal behavior.
Men and women are emotionally different; by training.
Tears, pouts, whims, tantrums, grow up bisexually. A boy
of ten comes into the house crying; he has been worsted in a
fight. His sister enters crying: worsted in an argument. Each
meets with a different situation in each parent. The girl's
questions on current events generally call out special re-
sponses from parents : "Little girls are not supposed to know
about business," or, "What possible interest can you have in
politics?" etc.
436
FROM THE STANDPOINT OF THE NEWER PSYCHOLOGY
Men, to "understand" women, must be brought up as
women: play dolls, wear dresses, be coddled, petted, pro-
tected, favored, shielded, guarded, restricted, chucked under
the chin, kissed. And thereby driven to such outlets as are
open to women and have no more "expected" of them than
men expect of women.
"Shades of the prison-house begin to close upon the grow-
ing child," as Wordsworth saw it. There are two: one for
each sex. With different opportunities, their impulses will
be conditioned along different lines. Given diflferent tools,
their pursuits will be different.
About sixteen years are required to train girls to certain
"womanly" needs and desires. Thereafter it requires some
one man's lifetime to satisfy these desires. If women de-
generate or go in for luxury, they are only following their
bent; their training "fitted" them for such paths.
Many men think such paths natural to women, and find
themselves "adjusted" when they hang a diamond dog-collar
about the neck of a woman who finds her life adjustments in
luxuries from another's hands. She has given all she has for
all she wants. That is adjustment. Life learns such behavior
as readily as other forms.
The two sexes may "grow up together," but they travel di-
vergent roads. By the time they mate they are likely to find
themselves far apart. Even words have different values;
they may not understand each other's language. But if their
habits have not been abnormal, and if they retain the capacity
to learn and the inherent love for knowing, a whole new
world confronts them. They can begin all over again, and, as
children, explore together to the ends of their days.
After all, there can be nothing in a man's world more inter-
esting than a woman. That man is "by nature" polygamous
and woman monogamous is biologic rot and has no more sanc-
tion than the Divine right of kings — and will eventually go
into the same discard.
Are women as efficient as men? Efficient for what? And
437
WHY WE BEHAVE LIKE HUMAN BEINGS
if not, why not? Why am I not as efficient as Charlie
Chaplin, or Arthur Somers Roche, or Jane Addams?
All normal newborns are efficient. After a few years, little
sister can never become as efficient as little brother in many
things. A woman requires a stout heart to dare to compete
with a man. Her own sex says, "You should not"; the other
sex says, "You cannot." If women follow the "easy" path,
it is because that is the only path in which they have been
trained to show efficiency.
If your water pipe bursts you do not need "efficiency" : you
want a competent plumber. Same way in seeking a mate. If
good ones are scarce, it must be for lack of early training
which fits for mateship.
Biologically, man must mate. Why men marry is a matter
of individual behavior. If marriage is a "failure," as we
are often assured, it must be for the same reason that any
other social institution "fails." Man learns new ways to
adjust to living impulses.
7
It is biologically important that the sex-complex leave
nothing to chance. It must function, as must the food-com-
plex, without having to stop to learn or acquire habits. This
implies a sensori-motor mechanism with preformed reflex
arcs ready to respond to adequate stimuli. The original im-
pulse for adjustment is within the individual organism. The
kind of food the organism ingests to complete the hunger
reaction will be conditioned by circumstances; as will the
mate by which the individual makes adjustment to the mate-
hunger impulse. In either case the impulse drives tlie in-
dividual. There may be neither food nor mate within reach
of eye, ear, or nose: the animal fares forth. The stimulus
is an inherent biologic hunger of the body.
The diff'erence between an eighteen-year-old buying flowers
and a twenty-eight-year-old buying flour is ten years ; both are
normal situations.
438
FROM THE STANDPOINT OF THE NEWER PSYCHOLOGY
It is psychologically significant that children of both sexes
are born with erogenous zones which from the beginning may
be excited by tactile stimuli originating outside the body.
This is in keeping with the biologically important fact that
the sex-mechanism is inherently perfect at birth. The impulse
for a mate appears later: at puberty. Meanwhile the second-
ary sexual characters make their appearance. But the mech-
anism itself is so built into our structure that inaction is
biologically abnormal. Yet we speak of "control"; and dose
youth with endless formulae.
One, I shall not soon forget. In a class in Christian Ethics,
we were being lectured on the "iniquity" of certain per-
formances. "But," protested one bold student. He got no
further. The president's face flushed red, and, shaking his
finger at the boy, he bellowed: "Young man, such ideas will
lead you down to hell!" Perhaps. But it is yet to be demon-
strated that the data of biology or the physiology of the re-
production-complex ever led anybody astray, much less
"down-to-hell."
Nature is not to be swept aside by bellowings or by any
"down-to-hells." If nature listened to argument and heeded
threats and could be scared out of her boots by every man who
claims to speak for Providence, she could shut up shop and
go out of life.
Man is a marrying animal. He gets married because he
is born that way. Nature spent millions of years perfecting
the marriage mechanism so that it could function on its own
reflex arcs and give man time to use his head to invent cattle
and corn so that he could have time to educate his children.
Man comes along and invents prostitution, celibacy, and other
sex-psychoses, and turns his children over to celibates to be
educated.
What happens to the sex-response mechanism between birth
and marriageable age? Biologically, nothing: nothing is ex-
pected of it. Usually nothing does happen to it to make or
mar later normal behavior. Man is born so sane that only
439
WHY WE BEHAVE LIKE HUMAN BEINGS
extreme conditions, sudden changes, or habits so distorted
as to make normal behavior impossible drive him insane.
The baby is rocked, petted, bathed, trotted on the knee. The
erogenous zones are stimulated. "Nursing and fondling are
not without sex stimulating effect," says Watson. The child
loves to be rocked and trotted. It forms attachments, con-
ditioned reflexes. The baby requires 150 days to find its
feet and toes. Another 150 days to discover its own organs.
This is a real discovery, but the child shows no instinctive
tendency to touch. But after these zones have learned the
nature of stimuli and the child has discovered them, dis-
torted habits may be formed. Their own developing bodies
may become objects of undue attention leading them into
emotional attitudes. Habits and attitudes take many forms.
They may become so fixed and so perverse that the child
will have no adequate mode of adjustment response to normal
sex stimuli later.
Sometimes normal physical development proceeds apace
with weird theories of the functions of sex, driving in harm-
ful attachments. The emotional wave which accompanies
development, having no normal outlet, may be sublimated
into art or any other emotional occupation; or it may be
perverted and become a psychosis. Normal behavior in
marriage is never experienced during some lives. No
woman naturally hates men; nor is it in man's normal reper-
toire of response to hate women.
While the original impetus comes from within, the
adolescent child finds itself in a world of sex stimuli. To
the growing boy all girls are girls: objects of special interest.
Naturally, not all make the same appeal. But throughout
life we continue to react and keep eternally reacting to the
fact that there are two sexes.
There are many ways of being abnormal, but no man or
woman can be entirely normal for whom the bisexual world
is without stimulus to normal reactions. Celibates, prudes,
440
FROM THE STANDPOINT OF THE NEWER PSYCHOLOGY
puritans, and old-maids-by-choice, have habits of inhibition
or of restraint beyond the limits set by Nature.
A bad habit is broken when replaced by a useful one.
Childhood and youth are habit-forming periods. Childish
habits stay with us or are replaced by others; but an old
habit is not easily shaken off. As James said of Rip Van
Winkle, who excused himself for every fresh dereliction by
saying, "I won't count it this time": "Well, he may not
count it and a kind Heaven may not count it, but it is being
counted none the less. Nothing we ever do is, in strict
scientific literalness, wiped out."
It is natural for the boy to pattern his reactions toward
his mother after his father, for the girl to "prefer" her
father. These innocent tendencies may be shamed into per-
manent attachments, making it difficult for the boy or girl
later to make perfect substitutions.
It is a boy or a girl that is born and grows up, not a food-
complex or a sex-complex or a motor-mechanism for playing
the piano or hurdle-racing. The boy or girl grows up all
together: parts develop or rust with use or disuse. Fingers
may learn to pick pockets as readily as pick berries. There
are many ways by which the sex-complex may take on habits
of no social value to the possessor and of no value to society.
These habits are not broken by "Don'ts" or bars. They are
backed by a high-strung mechanism wound up for preserving
the race. When this mechanism does not function one way,
it finds another. Nature backs it; training prepares the
channel into which it will direct its energy.
8
There are many histories of marriage. Westermark's, in
three large volumes, is a mere sketch and was out of date
the day it was printed. New marriage customs have been
invented.
Marriage does not stand still. It grows — backward, for-
441
^HY WE BEHAVE LIKE HUMAN BEINGS
ward, up and down. There are as many forms of marriage
behavior as there are married couples. Possibly more:
some dissolve and remarry. Marriage laws vary from state
to state, nation to nation, age to age. Can marriage behavior
be generalized or reduced to law?
There is no biologic excuse outside structural deficiency
for unmated adult human beings. Many human societies
respect that law. Other communities flaunt it, disregard
puberty, indefinitely postpone mating or mate casually, and
make the best of children as they do of other accidents.
In other words, we get little light on human marriage
behavior from the Mind of the ameba or the Social Instincts
of the anthropoid apes. Human marriage behavior is as
distinctly and peculiarly human as is a sewing machine or
the "Wedding March" of Lohengrin. The mate instinct must
be there: is there. If we are born whole, we have it: the
capacity to seek a mate, the impulse to find one if it takes
us overseas.
Why, then, a world of sexually unadjusted: unmarrieds,
divorces, oft-marrieds, courtesans, prostitutes, homosexuals,
asexuals, dog-lovers, snake-charmers, cadets, loveless mar-
riages, childless marriages? Endless kinds.
Two general observations: (1) Europe's population has
doubled in the last hundred years despite the enormous
losses from wars, disease, infantile mortality, and drains
overseas. The mate-hunger is not impotent. (2) We hear
only of the sexually-unadjusted. There are millions of
happily mated couples in America who find no fault with
nature's marriage laws or those recorded in codes.
Now for the other side: the behavior of the mate-impulse.
It leads many to marry. The marriage fails: drunkenness,
cruelty, infidelity, desertion, etc. The courts recognize
many grounds. Why does one man become a drunkard,
another beat his wife? Marriage itself is no more respon-
sible for such misfits than is business for arson or banking
for defalcation. The man who beats his wife probably beat
442
FROM THE STANDPOINT OF THE NEWER PSYCHOLOGY
his sister or his mother. The man who drinks because or in
spite of his wife would turn to drink under any other situa-
tion to which he could not adjust himself.
A larger mismated group is based on the polygamous
habits of one or the other, generally the man. In sowing
wild oats he scattered the energy with which he was endowed
to secure a mate; and acquired the polygamous habit. After
marriage he may acquire the monogamous habit; he may
not — ^his emotional nature will not so easily find sufficient
outlet in one woman. He also learned another habit: that
he could get what he wanted only if he translated his wish
into action. That lesson has great value, but is of no use
in marriage unless he wants to be faithful to one woman.
To make that want effective he has to break himself of an
emotionally-reinforced habit.
The other side of that picture is the woman whose early
mate-hunger was put on ice by a prudish mother. If she
is brought up on kisses and kisses all her girl friends every
time she sees them, she wastes a lot of emotion of biologic
value. She overflows with sentimentality and has no love
left for anybody. Or she grows up a "pure and innocent
girl." She has no adequate response in a situation where
a mate is wanted. Sheer ignorant "innocence" is no match
in a situation where the man knows too much. Neither senti-
mentality nor ice is fit response for the facts and emotions
of sex.
Between the age of fifteen and twenty-five are ten long
years. During these years the mate-hunger impulse cannot
be put to sleep, as one does a child; or locked in a closet,
as one does — but should not — a naughty child. It is
inevitable that huge amounts of energy be diverted. But
where? What is to be its outlet?
"Raise the standard of men's morality!" But not by talk.
Work will do it. Many a boy is so hard at work he has no
further energy left. His sex-impulse is expended in life-
443
WHY WE BEHAVE LIKE HUMAN BEINGS
impulse activities. Girls begin to find outlets for their
energy in action, in sports and games, and in the broader
affairs of life interests. All-night dances can dissipate a
lot of energy for both sexes.
The boy or girl who for ten years chases pleasure as the
main business of life may be "pure," but neither will be
likely to acquire any socially useful habits during that time.
Both men and women can become such habitual flirts that
they are abnormal; they are sexual perverts.
The normal sex-complex can be broken in many ways:
disappointment in love, no response on the part of the mate,
etc. The sex-complex thus becomes conditioned to abnormal
methods of response: tendency to avoid or be disgusted under
conditions which are neither "disgusting" nor to be avoided ;
prudishness; sloppy sentimentality; morbid interest in the
externals or accessories of sex conduct.
The sex-complex thus comes to mean for one individual
one thing; for another, quite something else. It comes to be
as varied as behavior itself. What it is at any one time
depends on the lessons it has learned: its experience, its
habits. No man or woman enters into marriage with a sex-
complex slate on which something has not been written.
Until recently, it was likely to be too little on the part of
the woman, an ignorance so ingrained that learning was
painful; too much on the part of the man, more than he could
rub off.
Foundations of habits (which means character) are laid
in homes. Nine-tenths of the girls that enter juvenile courts
leave bad homes. As Thomas puts it, many a girl cannot
be said to fall, because she has never risen. She is not
immoral, but a-moral. The mate-hunger is turned into love
for adventure, clothes, theater, attention, distinction, freedom.
And some discover that the only means they have to realize
these acquired appetites is their sex. They use it as they
would a coin to buy advantage and pleasure. Thomas cites
444
FROM THE STANDPOINT OF THE NEWER PSYCHOLOGY
Dumas as saying that girls in Paris lost their virginity as
they lost their milk teeth : they could give no plausible account
of the loss.
Or they marry with that same coin or buy entree to the
stage or a trip to Paris. Having chosen the easier road,
they soon become habituated to it. Until recently, women
had almost no incentive or opportunity to attempt achieve-
ment in male fields. Why should she when for every woman
there was a purchaser; for some, many bidders.
Until recently, it was a woman-made world we lived in.
The mere male had to go outside that world to work off his
surplus energy. The wife-mother was the center of the
home and it was to her interest to make it a real center. It
became a hive of industry and a swarm of children. What-
ever glorified it magnified her importance. Within, she was
supreme. In this woman-made world men passed half their
lives; the other half was spent in bringing home the bacon.
Women generally married for love, as they do now if their
mate-hunger is unimpaired and they are free to marry the
"man of their choice." There were three categories of
women: married, old maids, and "fallen." Thousands of
American communities had no "fallen" and next to no old
maids.
Now women have their "rights." In obtaining "rights"
she abdicated a throne: she no longer rules by divine right.
The children that "bless the home" are turned over to the
nurse while mother presides at bridge, over Conventions for
the Proper Care of Children, over Committees to Cleanse
the Slums. Result: males no longer naively accept matri-
mony or implicitly trust their wives; females turn to
matrimony if they have nowhere else to turn.
All this, of course, makes for "progress." But in our
social progress we have acquired special schools where boys
may learn to be pimps and girls to be prostitutes, and slums
which in squalor, vermin, filth, and disease, and in the num-
445
WHY WE BEHAVE LIKE HUMAN BEINGS
ber of their dope-fiends, pickpockets, paupers, degenerates,
hags, and harlots, are quite as "advanced" as those of Paris
or London. It is no longer necessary to go abroad to see
"life"; Babylon has moved to Main Street.
Social conditions are changing, but the average American
girl still approaches her majority fitted for no economically
independent career. Brought up as a social parasite, it is
her belief and the all-around understanding that marriage
is her career. For that no special preparation is deemed
necessary. She is a girl: what more can one ask? Few
men ask more. Some do not get a whole woman. More
rarely does the woman get a whole man. But sauce for the
goose is not sauce for the gander in these days of holeproof
socks, built-in beds, meals out, and no babies allowed; the
gander may feel that as meal ticket he is entitled to a dif-
ferent brand of sauce.
To say that the mate-hunger is greater in one sex than in
the other is nonsense. It takes different forms in the two
sexes because of training and the situation. Nor are men
less fond of children than are women. Having wider inter-
ests, they are bored sooner. In the divorce court the man
fights as hard as the woman for the children. If there is
any radical difference in sex-morality or marriage behavior —
or any other kind of behavior — in the two sexes, the cause
will be found in the way the two sexes become trained and
organized for life and in the demands society makes on
them; not in their inherent impulses.
Mamie, don't be a tomboy!
Many a mother these days nearly "dies of shame" when
Mamie bobs her hair and marches off in the garb of a Girl
Scout. "Girls didn't do such outlandish things in my day!"
They did not. We have to learn anew what our stone-ax
ancestors knew: girls can be as "outlandish" as boys! The
girls themselves are just beginning to discover it. Marriage
behavior is in for further conditioning. The sex-complex
may become simple again.
446
FROM THE STANDPOINT OF THE NEWER PSYCHOLOGY
9
A psychosis is a morbid mental state. We all have our
little psychoses. That so few have big psychoses, that so
few asylums are required to house the mentally unbalanced,
is a tribute to our sound inheritance and our capacity to
preserve our balance in increasingly complex situations and
an environment which changes faster than man can change
his mind.
My chief psychosis is, let us say, a morbid love for dogs.
I "shudder with horror" at the sight of a dog-fight. I loathe
the dog-pound and am the deadly enemy of the dog-catcher.
I defy the muzzle law — openly when I dare. I endow hos-
pitals for unadjusted dogs and cemeteries for dead ones. In
short, I am "crazy" about dogs. But as I am not a menace
to society, I am tolerated, even encouraged by "sympa-
thizers."
My own darling Fido dies. Now I am crazy. I buy a
satin-lined silver coffin with gold handles. I have a cere-
mony. Rites at the grave. Flowers. Et cetera. I spend
dry-eyed stony-stared hours at the grave. I refuse to go
home. I refuse to eat. My friends remonstrate: I heed
them not. It rains: I pay no attention. Nothing from the
outside world moves me. I am mad as a March hare. Ambu-
lance. Psychopathic ward. What "possessed" me? The
church calls it "devil" or The Devil. Freud calls it
"Unconscious."
There are as many kinds and degrees of psychoses as
there are of indigestion. There are few perennially sound
minds in perennially sound bodies; few of us that are not
oif our balance or off our feed now and then. Sometimes
it is serious. When we are off our balance, society suffers;
when we are off our feed, we suffer. Society expects us to
behave. And properly locks us up when our behavior is
dangerous. But if we die of indigestion, society is not
interested.
447
WHY WE BEHAVE LIKE HUMAN BEINGS
There are those who cry when they hear a dog howling,
smile when it wags its tail: the wail or gurgle of an infant
means nothing to them. Some children are thrown into
paroxysms of fear by a dog or a fur coat. Some cower from
lightning, and when the thunder roars overhead shut them-
selves up in a closet. I dodge an imaginary pump-handle
as I go by a certain spot. Few women would touch a snake
for "worlds"; some love and make pets of them. Some go
miles to see a prize-fight and are disappointed if no blood
flows. Whole nations go to bull-fights, knowing they will
see streams of blood. Some women faint at the mere sight
of blood; an English woman is insulted at the mention of it.
Psychoses? In a way. Such forms of behavior are not
"natural": they are no part of our inheritance. Every
peculiarity or abnormality of behavior and every psychosis
can be described in terms of individual experience.
It is the emotional side that bulges in psychoses: we
"adore," we "love," we are "passionately fond of," birds,
cats, dogs, bull-fights, pink tights, Niagara Falls, Caruso, tlie
night boat to Albany. Some "love" half the world of things
and all the world of beings. Others are as devoted to their
hates: they have dozens of ways for hating things and people.
Extreme and lurid fears are the third of the three emotional
Graces. A Grace in disgrace is a psychosis.
Whole nations get that way. We recently hated all Ger-
many, even "German silver" and Dachshunds; and loved the
French, down to snails and frogs' legs. We cheered at die
movies when we saw a German killed, applauded when we
saw a Frenchman kiss an American officer. The whole
"civilized" world suffered a huge psychosis: a kill-'em-love-
'em complex.
Freudian psychoses are planted in infancy and are sexual.
Freud even went so far as to say that every dream is a "wish-
fulfiller" and has its feet on the forbidden pleasures of
childhood.
The business of the sex-impulse is mating; if tlie two sexes
448
FROM THE STANDPOINT OF THE NEWER PSYCHOLOGY
do not pair, the sex-impulse has not attended to its business
and is a biologic failure. Many do not pair, few live happily
ever after; the sex-impulse has attended to everything except
its own business. Being denied proper outlet, it disarranges
society and long ago became the dominant force in human
behavior. By the time Freud is through, life is Sex. The
drive in life is love. Libido. "Thwarted libido" is respon-
sible for all the trouble.
That sounded interesting and Freudism became a fad;
then, a cult; and is now a disease and should be put out of
its misery.
Here is the argument. The newborn comes into the world
naked and unashamed. The world says: "That's not nice;
you must not do that." That begins the Conflict: animal
instinct versus social Donts. But instinctive "I wants" are
not to be laid by "Don'ts." What then? "Substitutes."
The young "mind" indulges its instinctive libido by symbols,
Society's substitutes for nature's actions.
For Freud, "mind" is stuff, a product of the processes of
development. Certain forces determine the trend of this
development. By "psycho-analysis" this "mind" can be
examined — as one examines the contents of a jug. Such
examination will reveal the manner in which these deter-
mining forces have acted and reacted.
But the mind is like a jug with much sediment below the
thin skim-milk on top. The sediment is the Unconscious
Mind, thick with repressed instinctive impulses and "I want"
memories. This stuff is a source of energy, loaded, always
smoldering; it exerts influence. It is a hidden drive to action
no less than the libido impulse itself.
Do the "repressions" ever rise to Consciousness? Only
when disguised or distorted — as they always are in dreams.
In dreams they "rise." But we do not know them, they are
so distorted, so symbolized. We must have a dream-book —
there are such ; or we must go to a psycho-analyst — there are
such. They can exorcise our big and little devils.
449
WHY WE BEHAVE LIKE HUMAN BEINGS
There are many physiologic and psychologic processes of
ameba and man which are not well understood, but Libido,
Unconscious Mind, Symbolism, or Idea, as source of energy,
is devil pure and impure. It is worse than feeding unknown
hormones to cure unknown diseases.
Science must formulate hypotheses — and proceed to test
them. But progress is not made by assuming that spanking
a child drives a libido to parts unknown which later will
jump up like a Jack-in-the-box to scare the man or woman to
death.
There are neuroses and psychoses: some with organic
lesions; some, morbid habit sytsems. The personality is
diseased: certain habits become so distorted that the indi-
vidual's useful habits do not suffice to adjust him to his
environment — home, society. These distortions usually start
in childhood: the child is spoiled, petted, babied, indulged;
learns to respond with lies, by cheating, by evasion; never
learns to accept responsibility for misdeeds. Such an one
may go through life with such habits. But let a crisis come,
a change for which he has no serviceable habits of response!
There are shades of unadjustment: instinctive behavior that
has never been taught to "behave," emotions that have
become so distorted as to be of no use to human society.
With inadequate adjusting mechanism, they turn to such
pursuits or practices as fall within the range of their capacity
to adjust.
No child is a "born liar." But a lively youngster may
become a proficient one in ten or less years, driven to learn
the art because parents will be parents and boys will be boys.
Every child is taught the meaning of approbation and of
contempt, and learns the meaning of candy and a hickory
switch. But few children learn that disguise, artifice,
deception, and falsehood have no value in "getting along"
with the family. The child does learn that simulation does
pay. If forced, it becomes adept in such behavior. Simula-
tion becomes an intrinsic part of its adjustment repertoire.
450
FROM THE STANDPOINT OF THE NEWER PSYCHOLOGY
The boss, the bully, the tease, the flirt, as well as the exhibi-
tionist, sadist, and masochist, are also specialized products
of vicious home or early school training.
The instinct of self-preservation may find a perverted
outlet in the impulse to be cruel to others. If continued, it
makes for sadism: f rightfulness, atrocities, prize-fights,
cruelty for the sheer love of being cruel, including cruelty
to one's own children.
Tlie sex-complex is complex in man and in all species
of animals with sexual reproduction. In human society it
has become increasingly complex. It is so individualized
that there are as many kinds of sex behavior as there are
individuals. So many things in life are '"loved" diat senti-
mentality is more common than sensuality. The inlierent
emotional drive to seek and love a mate goes out to dogs and
sunsets, and bathes with tears the belongings of the late
beloved.
Tliese are habits, types of behavior; they vary with age
and clime. Tliese habits fmiction in individuals. The sex
behavior of any individual is only to be understood in the
light of the manner in which the individual learned to
respond to the two-sex world in which he or she grew up.
To say that man is driven by sex is to say that man is a
mammal, or that human reproduction is sexual. To say that
a repressed libido is also a drive but hides in the Uncon-
scious— to pop out in a bad dream or a psychosis — is the
mystic's way of saying that life learns, and that reflex arcs
and salivary and other glands can be and are conditioned.
To say — with Freud and Jung — that the m}1:holog}' and
symbolism of human culture have their roots in tlie
Unconscious, is to make a magician's cave where by psycho-
analysis one can discover anything one puts into it.
'"Libido"' sounds more potent than love; "Unconscious"
more mysterious than behavior. That is why Libido v.as
so popular; why so many started to juggle with Unconscious.
451
WHY WE BEHAVE LIKE HUMAN BEINGS
10
This is the age of honest skepticism and the dawn of
enlightenment; even as it is of credulity — spawn of ignorance
and blind faith. But no age has been so capitalized and
exploited by fake science as are these States to-day. Fake
healers, dozens of kinds, hundreds of practitioners ; thousands
of suckers. A sucker is a fish that bites at any bait. The
healers do not even have to bait their hook. The larger the
hook, the keener they bite.
Develop your memory! Develop will-power! Learn how
to be successful! Improve yourself! Learn to read char-
acter! Personality experts! Psycho-analysts! Intelligence-
testers! Psychics! Even "Psychologists," on the Board
Walk at Atlantic City!
Body cures. Mind cures. Pills and pamphlets. The body
that runs forty years on bad fuel is not to be cured by
charms — whether in sugar-coated pills, elixirs, gland
extracts, massage, mud baths, mineral waters, or electric
batteries. Nor can the "mind" be "developed" in ten lessons
at $1 or $100 a lesson; nor by reading a "set" of books
or a year's subscription to some fake "psychological"
magazine.
Psychology is not magic, nor spiritualism, nor phrenology;
nor the science of the soul, consciousness, unconsciousness,
mind, or complexes. It is trying to be the science of human
behavior. It does deal with the reactions human beings make
to adjust themselves to change.
Is your own "mind," "will," "personality," or "character"
a collection of facts that you can analyze and count as you
can your fingers or the hairs on your hand or the buttons
on your coat? Do you mean anything to yourself apart
from your past experience? Every year of your life you
have built something into you — taken on new experience,
dropped out old ways of reacting to square with the new
452
FROM THE STANDPOINT OF THE NEWER PSYCHOLOGY
experience. Every reaction you make is conditioned by
former reactions and affected by the given situation.
We are going concerns, not hide and hair and flesh and
bones and instincts and faculties. Since birth, we are play-
ing upon and are being played upon by our environment.
The sum total of our personality — or "mind" or anything you
choose to call it — does not stay put. We cannot deposit it,
as we do money in a bank; nor sow it, as we sow wild oats
or tame wheat — and return later to gather the harvest or
burn the tares. Our personality does not stay put because
situations change endlessly. Personality without reference
to situation is as meaningless as a horse race with the horses
tied to their stalls.
Babe Ruth goes to the diamond and fans the air; Caruso
gives a performance he is ashamed of. Why do "stars" and
"champions" rise to heights of genius and at other times
drop into mediocrity? Do they know? Do you? Can you
predict what your game of tennis or golf will be to-morrow?
Or whether you will sell a certain party certain bonds or
insurance? You may have your selling campaign mapped
out: can you predict its success? The "certain party" may
have become quite a different party overnight.
In estimating both our own and others' personality, we
have to reckon with emotions, instincts, memory, habits,
sensations, age, experience, etc. These are variable
factors. I am older to-day than I was yesterday; so much
may have happened to me that I may not be the same person.
Parents often suddenly realize that they do not know their
own children.
Wherever our "mind" goes when we die, it certainly goes
with us while we live. I can read your mind "like a book"
only if I have all the pages: and for each individual there
are millions. I can test your capacity, or your intelligence,
or your will, only as I can pick a winner at the horse race. I
know at the end of the race.
You can sell goods: you prove it by references. You may
453
WHY WE BEHAVE LIKE HUMAN BEINGS
fail utterly to sell my cigarettes or my talcum powder. Your
intelligence may be A. B. with Highest Honors: you may
vote like a moron, fail as husband and father, mow the
flowers instead of the lawn, and prove a dead loss on a
camping-out party. As for will: it is as "free" as air. And
much more difficult to catch. I can develop as much will by
lessons on will-power as I can develop water-power at Muscle
Shoals by reading Coueism in a newspaper.
You and I do not, cannot, see the same things. We do
not see from the same point in space or time. Our eyes are
not the same. We see only what we think we see. Your
experience is your experience; mine is mine. We learn by
experience. Our capacity to learn is the measure of our
intelligence. Intelligence as so many yards of this and so
many pounds of that at so much per, may qualify a lad for
clerk in a notion shop, but furnishes no measure of the lad's
behavior outside that shop; or within, in case of fire, hold-
up, or fainting fit of a lady customer.
Sensations. Special sense organs: eyes, ears, nose, etc.
I have my nose, you have yours: Limburger cheese — same
sensation? I have ears, you have ears: a baby cries — same
sensation? I have eyes, you have eyes: a woman smiles —
same sensation?
What is a stimulus? Cheese? Not after I have smelled
it for an hour. Remove it: now it is a stimulus. A crying
baby? If it cries for an hour it is a great stimulus. If it
is yours I could murder it; if it is mine I telephone the
doctor. We read the same column in a newspaper: as a
result I buy SOS, you sell SOS. Another column may
send me to sleep, send you to Europe.
Stimulus is change. Throughout life, any and every
change in environment excites us if our experience — and we
inherit much — teaches us that we should make response.
Our psychology is human, but our behavior is individual ;
for each of us, the aggregate of inherent capacities and
experiences.
454
FROM THE STANDPOINT OF THE NEWER PSYCHOLOGY
One can read one's own mind — in the light of past expe-
rience; predict one's own accomplishments — in the light of
past achievements; and develop one's own will — by prac-
tising instead of preaching.
Psychic power? I know what power is; I know what
psyche is; I also know that knowledge may be power. But
I can discover only one way to get knowledge into my head:
through my sense perceptions. And only one way to get
any power out of that knowledge: by inference, by reason.
When my inference is bad, my reasoning is faulty; I have
only my pains for my trouble — my power-plant ground me
no grist. When I want magic power, I go see Houdini.
11
All processes of thought function through reflex arcs which
become conditioned, especially in childhood, and which tend
to become habits. We learn to think logically just as we
learn to speak correctly or to behave decently, I may think
well, I may shave well — who shall say? My way of shaving
and my way of thinking are my ways: the ways I have
learned; they are my methods of response to certain stimuli
in certain situations. I may change both to-morrow; some
one is always inventing new ways of adjustment, new ways
to excite human protoplasm to change its shaving soap.
New thought also. Why not? We have new foods, new
scandals, new songs, new elements, new diseases, new
razors, new glands, new logic. New things to think about.
The new grows out of the old — as corn grew out of wild
grass, or as a submarine grew out of endless discarded
models, or as chemistry grew out of alchemy, or as a poem
grows out of tryings-out of word combinations. Trial and
error.
The point is that there is no thought without muscular or
glandular activity; this is true whether the stomach thinks
hunger, the dreamer thinks air-castles, the prisoner thinks
455
WHY WE BEHAVE LIKE HUMAN BEINGS
freedom, or the maiden thinks of her lover. Thinking is a
bodily act, as is coughing or scratching one's head. During
thinking energy is consumed, mechanism is involved; and,
as a rule, the whole body is interested and is listening in.
Can we listen in, can we read thought as we can test blood?
Only when we can see it: as poem, as picture, on the golf
links, behind the counter, at the ballot box. By works. Overt
and explicit action. Money talks also.
But suppose no money is forthcoming, how can we know
what he thinks about it? Overt explicit behavior is easily
enough detected and is often of less consequence than the
implicit response. I ask you to lend me five dollars. You
hand it over. That is an explicit act. But your implicit
reaction may be of far greater consequence to me: you may
think me a cheap skate and decide to cut me from your list.
As you give no sign of such resolve, I cannot know that my
"Lend me . . has cost so much.
Of course, if you have looked it or muttered it in thought,
I may be able to read your face or your lips. I may even
suspect, with no overt sign on your part, that my request has
moved you to more than is involved in handing over the
bill. I question you; you deny that there is anything the
matter with you.
As we all do at times. As the run-in suspect does. His
face is a perfect mask for innocence. His self-possession is
complete. He is wrongly suspected! He is innocent! The
"third-degree" often breaks the mask and upsets the self-
possession. More often the third-degree fails or is not
available.
Many methods have been tried out to read minds tliat
would not be read, to detect an implicit response where tlie
overt side had only been suspected. All these methods go
on the justifiable assumption that what the individual does
registers in the individual dynamic mechanism. Apply the
proper test: the mechanism will yield its secret.
An extreme case will illustrate the methods. Suppose I
456
FROM THE STANDPOINT OF THE NEWER PSYCHOLOGY
return unexpectedly to my store some night, to discover my
partner in some questionable act. We quarrel. And I kill
him. Then cut his body up and dispose of it in the furnace —
an extraordinarily difficult thing to do, but just suppose that
I succeed.
The anger which prompts murder is an emotional impulse.
There will be occasions and situations in which I shall have
to be a man of iron to keep my emotions from betraying
me. Charged with the crime, they might lead to changes
in my respiration and vasomotor organization; even to
increased sugar in my blood and urine.
Or in my reactions to words. Woodworth has devised an
emotional questionary to serve to detect implicit behavior.
There are two types of word reactions: the free; the con-
tinuous. In the free, words are fired at the subject one at a
time. He is to reply with the first word that pops into his
head suggested by the word used: bull — moose; rat — trap;
pen — ink; teapot — dome; etc. Then comes a word which
brings no response from me, or I am unusually long in
reacting to it, or too quick. Or, if I am a girl suspected of
being in love, I giggle, blush, or drop my eyes.
The continuous type throws all the work on the subject
investigated. Only one word is shot at him: he is to reply
to his own replies. One word will suggest another; until
the subject stops — blocked, as it were. Then a new word
is given to start the subject off again. And again he seems
to run out of words, is blocked. Do the lines converge? Do
I always stop short of "murder," or "furnace," or chopping
up a human body? Is my free association of words shorn
of its freedom wherever and whenever I approach a word
which suggests the emotion or the deed I am trying to
conceal?
Dreams also may yield valuable clues to the nature of
personal stress and general emotional life. Also postures,
attitudes, over and under reactions, poor adjustments, slips of
word or pen, fumbling over names. But clues only. More
457
WHY WE BEHAVE LIKE HUMAN BEINGS
often the "tests" fail completely — though they may lead to
confession.
Conscience does make cowards of us all and habit keeps
us straight or crooked; fear of consequences makes us cover
our tracks.
"Reading the mind" is a figure of speech. The cashier of
the First National may be a good reader of counterfeit
money. I dump a bag of cowrie shells on his desk. Cowrie
shells are money in some parts of the world. Some of my
cowries are counterfeit. Can he read them?
12
The great by-product of our participation in the World
War was the startling discovery that "America is a nation of
morons!" Moron means dull or stupid, and is technically
applied to children with permanently arrested mental devel-
opment. Defective mentality due to congenital deficiency
is "amentia"; if due to deterioration, "dementia." Con-
genital imbecility is generally accompanied by a thin and
poorly organized brain cortex.
Nearly two million American adults were tested by the
army as to their intelligence. The average was that of a
normal school child of twelve. As the test sampled the
nation, the cry went up, "Nation of mxorons!" And much
bunk was and is talked and written.
What is intelligence? "Ability to learn or to profit by past
experience?" All right. The hog is an intelligent animal;
rattlesnake also; likewise hookworm and clam. "Civiliza-
tion's" intelligence, measured by the amount it has profited
by past experience makes a poor showing; it goes right on
putting its troubles upon the Lord instead of upon itself.
Voters make the poorest showing of all: they put their trou-
bles upon the "government."
The army had to find out whether a man could react to
orders and learn to use a musket; if not, he was not intelli-
458
FROM THE STANDPOINT OF THE NEWER PSYCHOLOGY
gent enough to shoot or fit to be shot at. If, on the other
hand, he knew the chemistry of explosives, he was too intelli-
gent to be shot at and was put to work in an ammunition
laboratory. The army had to make tests. It used certain
lists of questions.
I give you a list of questions. You may flunk completely.
Have I tested your intelligence? Only to the extent of that
particular list. Even then I have tested nothing of your
capacity to learn or to profit by past experience.
I have a bottle of liquid before me. I ask that bottle
certain questions: Are you indican, creatine, glucose, or
uric acid; have you any phosphates, calcium, or iron, in you?
To each the bottle replies "No." Very well, then, I cannot
use you; your mother did not bring you up to be a soldier.
But do I know from that test what that liquid is, or what it
will do if I drop a hair or a lighted match in it? Or what
it will do to me if I drink it? That bottle might be aqua
vitce itself, for anything I know to the contrary. I did not
test it for aqua vitae, only for urine.
There are idiots, imbeciles, morons, all degrees of feeble-
minded. Grade A feeble mind passes into the low grade of
a mind that is not feeble; and so on up through the grades
to genius. But there may be two reasons why I cannot talk
Chinese: never tried to learn it; could not learn it.
The deviltry of intelligence tests is the cold assumption
that there is something missing in the headpiece of the boy
of twelve who fails to make the grade, or that the adult of
thirty with a twelve-year-old grade could not have qualified
for college.
A Zulu "cannot count above four"! Awful! What a
moron! He owns a hundred head of cattle. Steal one. He
knows it is gone: he has a name for every beast he owns.
I am "good at figures." With slate and pencil I can tell you
how many minutes there are in a year. A Chinaman will
reach the answer in less time and more certainly by playing
459
WHY WE BEHAVE LIKE HUMAN BEINGS
with some buttons on some wires. An infant prodigy will
do it in his head — right off — just like that.
We start with suppositions in judging character, intelli-
gence, personality. We must, of course. But as long as
we are at the mercy of our convictions, we fail to realize
that the boy of twelve does not make the grade because he
cannot but usually because that grade does not appeal to
him. We have our own grades. The school, on the other
hand, has its own. Instead of attempting to find out what
grade I can make, it throws me out for not coming up to its
standard. The average man meekly accepts the verdict
incompetent, and is counted with the morons.
Every individual at any given age has actual and potential
assets and liabilities. He is either adjusted to his environ-
ment and has the equipment for readjustment when the
environment changes, or he is not and has not. He may not
be a sissy to-day; would he be a sissy under any situation?
He bites his nails, spits aimlessly, fumbles his nose, flies
into a rage, collects shells, is upset by a worm, shies at girls,
cheats at marbles, is always tardy: will he carry these habits,
bents, hobbies, and emotional attachments and antagonisms
to school — and out into life?
Many a teacher's time and patience spent trying to make
the boy or girl learn could be better spent trying to find out
what the boy or girl has a will to learn. Will being a human
engine that goes best with certain fuel and in certain direc-
tions. "Music lessons" have spoiled many a cook and
"modern languages" many a farmer.
If America is a nation of morons, then that is the answer
to the attractiveness of the intellectual feast our educational
system spreads; it is not a test of the American's ability
to learn.
We are cars of many makes, types, styles, gears, and motor-
capacity. Some are racers and some are trucks; some are
no good on dirt roads and some are tractors and can climb
mountains; some are one-seaters and some are buses; some
460
FROM THE STANDPOINT OF THE NEWER PSYCHOLOGY
can pull only themselves, others the whole family; some use
a pint a mile and some a barrel.
And as any car can be wrecked as it leaves the factory,
so also by careful and scientific handling every car is good
for its capacity.
But we are more than machines; we make ourselves as
we go.
Is this also a measure of intelligence?
What we make ourselves into depends on many factors.
But one consideration should not be overlooked: there is no
absolute in the measure of intelligence, only standards —
yours, mine, this community's, that society's, etc. These
standards vary and keep varying with time and place.
Christopher Columbus could not qualify for a water-tender's
rating in the navy of Alfonso XIII. Of the world's hundred
geniuses perhaps five could pass any of the contraptions now
in vogue to measure intelligence. Of this same hundred
few, if any, were rated "Intelligence Al" by their con-
temporaries. In fact, some of them were killed by their
contemporaries for lack of intelligence. Was that a measure
of the intelligence of their contemporaries?
13
During the month of August, 1914, a great nation lost its
character but gained a reputation.
Character seems to be an essence, a spirit, a core, a stuff,
that defies analysis: like Consciousness or Unconscious Mind.
"If I could only get at his 'true character,' " we say, as
though it were something quite beyond range of investigation.
Or at least beyond anyone but a psycho-analyst: he might
be able to "draw it out."
What do we do with a bottle that "looks like gin but may
be poison"? Try it, or have a friend try it, or send it to a
chemical laboratory. Are there laboratories where character
may be analyzed? There are: palmists, phrenologists, hand-
461
WHY WE BEHAVE LIKE HUMAN BEINGS
writing experts, Freudists, mind-readers, clairvoyants,
Swamis, mystics, and charlatans — ignorant and honest or
wise and dishonest. They all "read" character.
While they are in the inner shrine with some one's "true
character" or "inner self," let us not forget that human beings
do not come like buttons from a mold but in individual
packages. There is probably a prize in every package, if we
only looked for it or knew how to find it. These packages
come with a limited repertoire of habits, an unlimited amount
of emotion, and an enormous capacity to learn. Further,
they are keen to learn: their very bodies itch for action —
they could not have peopled the earth and enslaved nature
otherwise. Further, these little packages, in the natural
process of becoming untied and budding like a rose or a
sunflower as is their bent, become more and more tied up.
With the result that by the time one is old enough to vote —
whether it has learned what the ballot means or not — it be-
longs to mother's church and father's party, and wears the
clothes, thinks the thoughts, and swears by the flag the family
and the community have wished on it.
In short, its "character" may be nil, its reputation fine.
But it is a person and is so recognized by law. It has a per-
sonality. It is a going concern. Where and how fast and
how long it goes, and when it will throw a fit or jump the
track or explode, depend . . . Fill in the details yourself.
We do, every day: Shall I marry her? Does he love
me? Shall we invite them? Shall I accept his invitation?
Shall we let her go to the dance with him? Dare I make the
venture? Is he fit for our son to play with? Is his note
good? Shall I employ him? Is she a good cook? Is he
an honest chauffeur? Would you, if you were I?
How do we answer these questions? Call in a palmist?
Some do, or there would be no palmists. But most of us
answer them as we answer other questions, such as: Wonder
if I dare eat that pie? Is it a real ruby? Is this a good
lipstick? Shall I buy Q. E. D. or sell P. D. Q.? Shall we
462
FROM THE STANDPOINT OF THE NEWER PSYCHOLOGY
send Willie to Brown or to Green? Is this road safe? Shall
we go to the movies or to church? Is the beer all gone?
Shall we quit now or play till morning? Is this suit good
enough? Shall I endow a charity now or steal another
million?
We make mistakes. With original sin loose in the world,
we must. We make mistakes in persons and things. "She
is not what I thought she was": which is correct enough, for
having met you she is to that extent different. "That is not
what I thought I bought": true again; but it is what you
were sold.
We learn by our experience. And some learn fast and
with profit, and others learn as little as possible. It all
depends.
But if we were "good" children and learned to jump at
father's orders, and to "respect" his authoritative manner and
commanding ways, and learned to smile and swallow "like
a good little man" the nasty medicine the doctor leaves for
poor little sick boys, we are likely later to listen with open
mouth to the man who pounds the platform or the pulpit or
fills the room with his magnetic personality! But if father
was a little runt without voice or influence in family affairs,
we are likely to overlook the personality in a shrimp,
A "pleasing," "thrilling," "absorbing" personality is one
we like to touch. Men shake their hands. Women kiss
them. When "I instinctively like that person," the instinct
that is talking is an unanalyzed sexual or emotional slant
based on early habits of love. A "lovable" personality
within the same sex is possible because sharp leanings toward
the other sex were not formed at the time sex matured.
Co-education is sanitary education.
We jump at our personality conclusions. We know he
cannot be this and she cannot be that. What we really know
is that some personalities appeal to us, others do not. We
can rarely give the real reason for our spontaneous judg-
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WHY WE BEHAVE LIKE HUMAN BEINGS
merits. Personalities are rather more complex than apples
or motor cars.
The most "erect carriage" may be the greatest social
scoundrel unhung. The "intelligent brow" may be housed
under a dunce's cap. The "squarest chin" may be a weak
sister and the most henpecked man in town. The "firm
mouth" may hide a flabby body and a soft head.
Some things do show through: elation, despondency, etc.
But the rosiest cheeked apple may have a wormy heart. A
woman with a homely face covers it with hat and veil or
tresses, and sells herself on her form.
Pick fifty men at random from Fifth Avenue. Take them
to the Tombs, shave their heads and photograph them. Mix
the photographs in with those of fifty inmates. Call in your
mind-readers and character experts. How many will they
pick out? As many as the law of chance allows them. Now
take the fifty inmates, dress them in the hair and clothes of
the new arrivals, and drop them along Fifth Avenue. Call
in your character experts. If they can pick these fifty
"toughs" off Fifth Avenue, they should report to the Chief
of Police of New York or the Attorney-General of die United
States. Jobs await such men.
People who read character from hands like to hold hands;
and vice versa. If they pay to have their hands held they
do not lose their personality, only their money.
John Stuart Mill speaks of an event which took place on
Calvary: "The man who left on the memory of those who
witnessed his life and conversation such an impression of his
moral grandeur that eighteen subsequent centuries have done
homage to him as the Almighty in person, was ignominiously
put to death. As what? As a blasphemer!"
14
Life is easily destroyed, but the matter of life is inde-
structible. Life easily tires, but the energy of life is not lost,
464
FROM THE STANDPOINT OF THE NEWER PSYCHOLOGY
Life is dynamic. When struck — as by blow of slipper or by
a chuck under the chin — a chemical reaction takes place;
that reaction alters its nature. It is now something else. The
change may be slight ; it may be so great that its very dynamic
nature is altered — the change endures for life.
Life is impelled to action because it is a reacting mecha-
nism: certain stimuli impel it to action. What life does de-
pends upon what life is; and that, in turn, depends upon what
life does. The life that climbed up to man never ceased to
recreate itself on higher levels. The oftener it reacts, the
greater the ease of action; practice makes perfect. But life
itself is not moved by perfection; with too much practice
it grows fatigued. Had life been content with mere per-
fection, it would have stopped with bacteria and algae. It
essayed more difficult roles and by greatly daring became
man. It could not have built up a nature so imperious for
power or so keen for experience had it been content to say: I
desire nothing more; I am perfect.
A perfect man is as finished a product of Nature as a
bacterium and may be fit for Nirvana, but not to rule or to
lead men. For men are of the stock that moved up out of the
slime and set no limit to their desires. They insist on action
because action is the nature of their inheritance. But they
must have new stimuli or they fall asleep with ennui.
We begin our life with a semifluid body of twenty-odd
chemical elements which surrender their original nature in
becoming welded into a compact organic system. This body
builds itself up into a vastly complex machine of billions of
individual bodies, each retaining something of its original
nature, each surrendering something of its original nature
that we may function as one individual being. The energy
which drives this machine is chemical, the impulse which
drives the machine to secure this energy is inherent in the
living protoplasm of our body.
Chemical reactions in a chemical body. Of some reactions
we are conscious, of most of them we are not conscious.
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WHY WE BEHAVE LIKE HUMAN BEINGS
But the living mind and the living body are inseparable and
together make up the individual. We never know what is in
our "mind," for the mind is the living body which because of
its nature must react to every vital change in its environment.
We can recall to memory only a few of these reactions: those
burned in. We cannot recall countless memories; we have
no machinery or organs for forgetting. Nevertheless, they
have left their mark; each reaction alters the protoplasm
for further reactions; it is never again the same. As the
universe itself is not made, but is continually being made, so
with man.
This view of universe and man is repugnant to many; it
disturbs the serenity of their belief in the Absolute and
Eternal and the simplicity of their thought that earth and man
were created, as a magician conjures goldfish out of nothing
and rabbits out of an empty hat.
Man's chief impulse at each moment of his existence is for
life: self-preservation. At certain moments food-hunger dom-
inates the self-preservation impulse, at other moments sex-
hunger dominates. But because of his capacity to supplement
his motor mechanism with tools, weapons, and appliances,
he was able to give his biologic impulses ever-changing out-
lets. He also developed language into a definite means of
communication, and thereby further extended the range of
possible responses to living impulses. Thus, on his repertoire
of animal adjustments to vital conditions he superimposed
a repertoire of human adjustments. The rise, development,
spread, and decay of these purely human adjustments make
up the story of the history of human culture.
The culture of any people, tribe, race, or nation at any
given time is an historical problem. Memphis, Troy, and
Carthage, of the Old World or the New, are riddles apart
from their setting, apart from the historic factors which
conditioned their development. The lives of Buddha, Con-
fucius, Socrates, Mohammed, Tamerlane, Elizabeth, Napo-
466
FROM THE STANDPOINT OF THE NEWER PSYCHOLOGY
leon, Washington, and Frank Smith, are also riddles without
their setting.
Each age carried its loaded situation to which human beings
responded in obedience to the impulse to live. Every age had
its modes, norms, habits, opinions, manners, customs, taboos,
and its written and unwritten codes of behavior. Mohammed
born on Beacon Street would have gone to Harvard and been
a Unitarian.
Every age thought itself wise and prattled of "progress";
and lagged from one to one hundred decades behind its own
wisdom. Our own national habits and social, educational,
legal, and governmental institutions jog along in ruts worn
smooth by our forefathers. There is not a city in the United
States organized as a community for the purposes of living,
almost no individual that practices what he preaches or puts
to useful purpose a tenth part of his brains.
A hand fitted by nature to swing from limbs and catch fleas
learns in five years to drive a nail and in fifteen years to
drive a car it took culture 100,000 years to make. One
wonders that culture required so many years to produce the
car; but one is amazed that so many children can learn to
drive a car in such short time. In other words, our civiliza-
tion as the "product of all the ages" loses much of its glamour
when view^ed against the background of what an ordinary boy
or girl can learn in twoscore years.
Tokyo, Peking, Delhi, Cairo, Rome, London, Nevv^ York,
Main Street: random sample worlds. Into these life comes
in small packages called babies, fundamentally all alike, all
human, all blood-kin, all of one species. They have the same
general adjustment mechanism in the same excitable proto-
plasm, with tlie same instinct for life and the same emotional-
drive equipment. And all have parents to tide tliem over the
infantile period until such time as their motor mechanism will
enable them to seek their own food, water, and shelter, and
in general make their own adjustments, including picking a
mate.
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WHY WE BEHAVE LIKE HUMAN BEINGS
These same babies one, five, twenty, fifty years later show
differences more than skin deep, differences burned into the
very protoplasm of their bodies. Which means: their habits
are different, their thoughts are different. They doff their
hats to different gods and play the game of life in dififerent
ways and for different stakes.
Contents of their mind? We can only answer that as we
know the conditioning of their mind: what they jump at and
why. Always remembering that individual variation sets a
limit to our jumping mechanism ; also that we know little of
that limit because it is restricted by fears and hemmed in by
taboos.
Into each home the baby comes as a loaded stimulus. It
may be hailed as the watcher greets the dawn; or with,
"Well, here it is"; or as another mouth to feed. Its arrival
is a complex of stimuli. Out of these the baby is often made
or broken the day it is born — a chance that must be taken
these days as the price of the opportunity to become civilized.
Most of them do. Some never become adjusted. They die,
as Socrates, Savonarola, Lavoisier; or they are fed to the
lions by Nero, disappear on Saint Bartholomew's Day, or
work in a factory. They borrow, beg, or steal. There are as
many ways and degrees of unadjustment as there are of ad-
justment, all graduated to the ways and degrees to which
adjustment is demanded.
In short, there is no knowing man without knowing men.
"Everybody's doing it" and "People don't do such things"
are collective reactions biologically useful in herds and early
human society, but they persist in countless forms to-day and
extend their influence to such unimportant biologic factors in
modern life as ruffles on skirts and creases in trousers.
"Everybody is" and "People don't" become potent factors in
modifying the environment to which individuals are con-
ditioned to respond.
Almost before the youngster has learned to respond to the
facts of life, he is compelled to learn adjustment to tlie
468
FROM THE STANDPOINT OF THE NEWER PSYCHOLOGY
fancies of life. Human behavior as adjustment is meaningless
without understanding the power of social environment to en-
force its limited responses upon the newcomers. Society does
not easily change its mind, because to change is to acknowl-
edge defeat; it hates to run. Its mind being its entire body
and tied up with emotion, it vents its hate on "Don'ts" and
much of its energy in enforcing obedience.
But there is almost no limit to the pressure that a normal
individual can stand if the pressure is applied gradually;
we get calloused: to odors, sights, sounds, and bondage of
trappings, and the harness by which we draw our burdens.
And well for us that we can become accustomed to the burdens
of things, people, and situations that we must bear. But man
is not by nature a beast of burden or fitted by nature to keep
his nose to a grindstone. And the man so yoked or chained
is one more human being lost for activities that might be
human.
As one recalls some of the monstrous situations under
which human beings have lived and live their lives, one
marvels at man's meekness and complacency. It can only be
explained by that quality of flesh to become calloused to
situations that if faced suddenly would provoke blisters and
revolt.
Man's inheritance is all right and is his only inherently
valuable asset. It is human behavior — individual, com-
munal, national — that can be changed. But not by cut-and-
dried programs of social reform; nor by reformers, codes,
ideals, or by our present "system" of education. Life itself
is not systematized or standardized: it wants to live, it wants
to enjoy life. It has a pain sense; it responds to love; above
all, it can learn. We start with that equipment. Herein lies
the significance of the new conception of human behavior; the
importance of the task that confronts the new psychology.
Organized society is — or should be — interested in socially
serviceable behavior. Its problem is to control behavior for
social ends and at the same time give the individual free-
469
WHY WE BEHAVE LIKE HUMAN BEINGS
dom to express and develop his innate capacities for normal
behavior. This cannot be brought about by chance; there will
be delinquents, abnormals, subnormals, as long as breeding
grounds for such are regarded as normal by-products of
social organization. The entire substratum of misfits will
disappear only when the environment is so changed that
misfits do not form part of its normal output.
Rational conduct is a dream. But conduct freed of sordid-
ness, of squalor, of haunting fears, of ungoverned tempers,
should be the possible fate of every normal child. We can
at least make this a better world for children to be born into,
and so alter their environment that they need not learn to
lie, steal, murder, or commit rape or bigamy, to succeed.
The seemingly infinitely large universe is made up of the
seemingly infinitely small units of electrons. The universe
is what it is because of the nature of their behavior under
the drive of energy. That same energy drives us. The units
of our social universe are human individuals; it can be
molded only as the individuals them^selves are molded. Liv-
ing beings are not elements, but reaction systems: their be-
havior can be molded. Ours is already set; but it is not
necessary that we condition our children to the mold in which
we hardened.
In the whole history of human thought there has been voiced
only one rule of conduct of the slightest value as a standard
for human behavior. It is applicable to individuals, families,
communities, cities, states and nations:
"As ye would that men should do to you, do ye also to them
likewise."
But note that you and I as individuals can never get a start
on putting the Golden Rule into practice until we have set our
own house in order. When we strip our unethical and in-
fantile hang-overs of behavior of their veneer of rationaliza-
tion we are likely to be astounded, as Watson points out, at
our "susceptibility to flattery, weakness, inadequacy, or lack
of knowledge, jealously, fear of rivals, fear of being made
470
FROM THE STANDPOINT OF THE NEWER PSYCHOLOGY
the scapegoat," and proneness to hurl criticism upon others
to escape it ourselves. The first step in setting our house in
order is to remove the beam from our own eyes — perhaps the
hardest task man ever set himself, certainly a task that can be
achieved only by the brave.
When human society starts to practice the Golden Rule, it
will lay a foundation for civilization which no flood of pas-
sion can shake. Any other conditioning of our inherent
nature leaves us as we are — with an animal nature modified
only by man-made devices to satisfy living impulses as old as
life itself. Man is the product of evolution; humanity must
be the goal of human endeavor.
15
Probably no two are of the same opinion as to what con-
stitutes socially useful behavior. But there can be no doubt
that many do not get out of life what life might be expected
to yield, considering the length of time it has been on the
job, and that many do not give to society the service society
might expect to receive, considering the energy it expends on
educational and social endowments. Why this is so is an
enormously difficult and vastly complicated problem. Is it
because society solves living with the latest mechanical con-
traptions and solves life with old rules? At any rate, it
knows next to nothing about life, but does have a large collec-
tion of gadgets for living. As a consequence, we are at the
mercy, and not in command, of the tools of living.
This is no plea for the "simple life" — or a remedy for
anything. Goodness knows, we have enough prescriptions,
and enough bandwagons and barkers inviting us to climb
aboard. But have we a sound diagnosis of social ills and
individual disabilities? Are our parents and teachers setting
examples of rational and intellectual living, and are they
getting into the rising generation such an outlook on life, such
a conception of the possibilities of life, and such a compre-
471
WHY WE BEHAVE LIKE HUMAN BEINGS
hension of the unlimited capacities for life, that the next gen-
eration will inevitably live a broader, saner, sounder, and
more intellectual life than we are living?
And by intellectual I do not mean "high-brow" stuff. I
mean the kind of intelligence that distinguishes men from
cats and cattle — what they think about, what occupies their
gray matter. There is no inherent reason why the miner,
plowman, and milkmaid should not be as intellectual as the
poet, auditor, or school-teacher. Coal, corn, and milk furnish
us more energy than poems, balance sheets, and schools. If
ignorance is bliss, all right. But this country proceeds on
the theory that ignorance is a defect, that education will cure
it, and that the opposite of ignorance is intelligence; and
that compulsory education makes for intelligence.
But does it? What has the boy or girl of intelligent be-
havior on leaving school? To say that they have a smattering
of this and of that is to say what everybody knows and what
has been said thousands of times: that they have added a
few hundred words to their vocabulary, have memorized a
few facts and formulae, have dissected a fishworm (possibly)
and a flower, and have read several hundred pages of history
and polite literature. That may be education, but it is not
life; nor is it hitched to human lives or human society; nor
is it intelligence.
Good, honest, hard-headed character is a function of the
home. If the proper seed is sown there and properly nour-
ished for a few years, it will not be easy for that plant to
be uprooted. But it is the business of the school so to engage
youthful interests that youthful energies will flow into crea-
tive channels. No school can really educate; but every
school should nourish the enthusiasm of every normal child
for learning, for exploring, for manipulating; should stimu-
late the fountain of youthful curiosity and not plug it up with
facts. Above all, it should not dam youth up — or down.
Youth has the will, the energy, the impetus; give it raw meat
and bones to chew on. Give it a place in the sun, keep it in
472
FROM THE STANDPOINT OF THE NEWER PSYCHOLOGY
touch with life, help it to get its feet on the ground and its
wits ground to a razor edge. To go over the same old ground,
to analyze the same old moss-covered problems, is dilettant-
ism; it is not preparation for life. This is a new world; it
demands new brains, and new people to handle the new prob-
lems of life and of human society, quite as much as people
trained in building bridges and motor cars or in selling lip-
sticks and bonds.
Socially useful behavior is not more prevalent because
socially fashionable behavior has a better lobby. Good Form
is in the saddle; it is ruthless, it is mighty, and it does prevail.
It is not founded on intelligence, it requires no brains, it has
no outlook, it is stupid and short-sighted, it incites to anarchy
and chaos. Education to-day is its handmaid and its body-
servant. As a propagator of unsocial behavior, the so-called
Christian Church, with its endless squabbles over forms,
creeds, and rituals, and its eternal betrayal of humanity, is
not far behind. By Fashion I do not mean the or a Four
Hundred; I mean those in power of money and of govern-
ment; our bosses; the people who are trying to make us buy
their wares, join their club, vote their ticket, think their
thoughts, and help them kill or cripple their enemies.
After all, what can be of less consequence to you than
whether I believe in this or that kind of a God, Saviour, gov-
ernment, society? What is of consequence to you, to society,
and to me, is what I do, I may be a socialist, an agnostic,
and incredulous of the Mosaic origin of woman from a man's
rib and of the parthenogenetic origin of the Christ and of
several other things you believe in. What of it? Why should
you try to convert me to your way of thinking? The fact that
you hold a certain opinion or belief does not necessarily mean
more than that you have inherited it from some simple-minded
ancestor, and that in being handed down it has acquired
sanctity — like a hair watch-chain. What is vitally more im-
portant is that I live as an honest human being who acknowl-
edges responsibilities and obligations, who plays the game
473
WHY WE BEHAVE LIKE HUMAN BEINGS
like a thoroughbred, who does not whine and does not cheat,
and who believes that there is room in this world for many
creeds but for only one religion.
The kind that was Lincoln's. Does anyone know what
Lincoln believed? The world knows what he did. He lived
his religion, day by day. As I recall a famous conversa-
tion started by an inquiring soul who wished to know how he
might be saved, he was not told to tell his beads or burn
candles or sing hymns or sign a pledge or subscribe his
name in a book or even to be baptized; he was told to do
something: to get in bed with humanity.
Is education attempting to encourage creative thought, or
merely trying to divert thinking into old channels and so
stifle it entirely? Thinking on old lines is to continue in the
same old way regardless ojf reason or intelligence. Thinking
soundly is to wake up and ask questions; it is to make new
creations possible.
I went through one school and was halfway through another
before I woke up and discovered that Lwas alive; that it is
no sin to question anybody or anything; and that there are
several problems yet unsolved! It was quite too long before
I realized the diff'erence between "That is so" and "That is
necessarily so"; quite too long before I realized that going
to college did not necessarily mean anything in particular.
Curricula change and lists of "electives" grow like weeds,
but the human nature in the professors and in the pupils re-
mains the same. The school merely demands that a certain
amount of a specified number of courses be absorbed; the
success of a course is measured by the number that take it.
The curriculum itself reads like a mail-order catalogue. No
conceivable course is omitted, except one on life and how to
get more out of it with less friction to others and less lost mo-
tion to the liver.
All this may sound like propaganda. It is. Propaganda
for sanity; for enlightment; for brain work; for time to live
and the acquisition of a few simple tools to live with; for
474
FROM THE STANDPOINT OF THE NEWER PSYCHOLOGY
understanding; for such charity as will abolish the need for
alms; for honesty in rulers and intelligence in legislation;
for a stop-and-think-it-over week; for regard for human
rights; for critical judgments; for dispassionate opinions;
for hatred of shams, intolerance, falsehood, and deception;
for riddance of quacks, mountebanks, impostors, charlatans,
vermin, squalor, and ignorance; for a car for every family
and a joy ride through life for everyone; for socially useful
behavior.
Everything that man has made, done, said, and thought has
been built on the impulse to live, organic hunger for food and
mate, fashioned, molded, and reinforced by the emotional
drive in life. Every normal human being has that equip-
ment at birth. It is in the very marrow of the child's bones,
in the protoplasm of its nerves. It is the foundation of every
personality. It cannot be wiped out, crushed, or stifled; it
can be warped, distorted, diseased, degraded. It can be
encouraged to grow, to expand, to blossom, to bear fruit. It
may produce an inspiring leader who will show the way and
be the way to bring a new order into the world of human
affairs. Society may kill him. Never mind. Society will
build a monument to him in admiration of his having dared
to be a leader. The least we can do is to keep our hands off
the courage of youth.
Emotional drives are not new in man, or even in Primates.
The newness, the uniqueness, are man's responses. Rage
and fear once led to fight or flight; they now supply the
drives which may lead to drink, to burglary, to murder, to
insanity, to suicide even. As Thomas points out, the day-
dreamer may become a scientist, a swindler, or a liar; the
adventurer, a vagabond, cowboy, missionary, geologist, or
ethnologist; the killer may shoot big game with a rifle or
with a camera; the sex-impulse may lead to a Don Juan, to
a prostitute, to a love-lyric poet, or to a lover of home and
family.
475
WHY WE BEHAVE LIKE HUMAN BEINGS
The problem, then, is such a reorganization of society that
socially useful behavior shall be at least as profitable and
interesting as unsocial or criminal behavior. Opinions may
differ as to the extent to which bootlegging, prize-fighting, and
prostitution are unsocial, but there is no doubt about the
profitableness of these professions — as compared, let us say,
with farming, preaching, and teaching school.
What is wrong with the picture? Each one, I repeat, will
have his own opinion and his own remedy — and will be ready
enough to express opinion and remedy, and back up both with
hot argument, if necessary. But what will he do about it?
Parents will continue to do business with unsocial or crimi-
nal professions, and teachers will probably labor in vain
for a living wage; but there is one thing both parents and
teachers can do: give youth the opportunity to become con-
scious of society, of human life, of humanity; encourage it
to think, to speculate, to revalue, to weigh evidence, to be-
come disgusted, to choose, to see through things, to see things
and life objectively. Critical consciousness.
How has "progress" been made in medicine, in chemistry,
in physics, in engineering, in all the respects in which progress
has been made? By doubts, by questionings, by testings of
hypotheses, by solutions of problems, by critical activity in
the human cortex.
Man is a free moral agent and can be magnanimous and
deal disinterestedly, humanity is a definite goal, social justice
is desirable and possible, individual lives may be gloriously
diversified, uniquely individualized, and yet socially useful;
or, these are mere phrases, snares to catch gulls, sootliing
syrup for troubled souls. Here again, opinions will differ;
but no one will pretend that society to-day is organized (as
a living organism is organized) or that social relations are
one whit more intelligently ordered than in the days of
Pericles or of Julius Caesar.
The problem, then, narrows down to this: children of
476
FROM THE STANDPOINT OF THE NEWER PSYCHOLOGY
nature and creatures of circumstance as we are, can we dis-
cover what organic evolution is up to and can we help it on
its way?
16
You and I and all living beings differ from dead things
in one respect: we grow, and by one process; we incorporate
inorganic and dead organic matter into our individual bodies.
Our nature is such that we are impelled to do this. This gives
us a clue to organic evolution.
For, note: the matter which must be incorporated within
our bodies is outside us; we must get it. During organic
evolution, it was not life that evolved ; it was the rate and the
kind of life that was lived; faster, freer.
The visible agencies finally evolved for the faster, freer
life were : motor mechanism of bony levers worked by muscle
engines; special analyzers or distance receptors; cerebral
cortex; and vocal cords and voice mechanism. These agencies
made for improved locomotion, more exact information,
more space for storing information, and improved facilities
for exchanging information. Accompanying these visible
agencies or tools for a faster, freer life, there evolved special
physico-chemical mechanisms for driving life — as though life
had grown a firecracker under its tail, as it were. These
agencies and the emotional-drive mechanisms man shares
with other Primates and to a large extent with all mammals.
Only, man's motor mechanism moves on two feet instead of
four; his hands are freed from the drudgery of footwork;
and his cortex is so vast that he can measure stars and elec-
trons, but not his own capacity for intelligent action. In fact,
his potentialities are as far beyond our powers of vision as
we of to-day were beyond the vision of our ancestor who in-
vented fire by rubbing two sticks together.
Are language and culture the inevitable consequences of
man's nature? Are they the goal of the faster, freer life
477
WHY WE BEHAVE LIKE HUMAN BEINGS
made possible by certain agencies and mechanisms? Is man
himself the finished product of an evolution which continually
created life on higher levels? The idea is worth manipulating.
Consider the emotional drive. Where has it not carried
man? To what heights and depths has it not driven him? The
fiery passion for life, the haunting fear of the unknown! The
ages-long persecutions, the massacres, the burnings, the tor-
turings, the revilings, done in the name of God to prove that
God is just! The hells that have been invented to scare
children into loving a merciful God! How the heavenly choir
must have wept — or laughed!
Death is a common affair in nature; for millions of years
man had been dying of old age or disease or killed in combat.
But he suddenly becomes conscious of death! And within a
few centuries he has raised a natural phenomenon to a vast
and complicated rite, and expects the very stars to stand still
while he breathes his last. The monuments to the dead, the
worship of the dead, the prayers for the dead! Yes, and the
communion with the dead! All this had to be, presumably;
man had become that kind of an animal.
It was inevitable that his curiosity should impel him to
explore his world, to manipulate it, to play with it and experi-
ment with it; that with hands he should tear down and build
up, that with voice he should fashion speech and with words
should remold the world to his heart's desire.
It was inevitable that upon his bisexual world he should
erect a family hearth; it was not inevitable that he should
invent this or that kind of household gods, or that upon that
hearth he rear a harem or found an order of celibacy or
vestal virgins. Or that he should worship his wife, or degrade
her to a parasite; or that she should make a fool or a criminal
of him.
It was inevitable that his love for life and fear of death
should lead him to magic rites and groveling superstitions;
it was not inevitable that his religion should be used as a
478
FROM THE STANDPOINT OF THE NEWER PSYCHOLOGY
cloak to hide his selfishness, justify his greed, and sanctify
his lust for blood and gold.
Culture, in short, was inevitable. Man was, man did.
Our evidence of the causal relation of tides to moon rests on
no more solid foundation. Once there were no Primates;
Primates came. There was no man; man came — and with
him came culture, little by little, slowly, painfully, gropingly,
even reluctantly at times. But it came: words to talk with;
gods to placate; rules and laws to break or obey; swirls of
family life ever growing larger; tribal organization and
states, torn asunder, being rebuilt, organizing and reorgan-
izing; music, art, literature, classified knowledge, science,
philosophy, moonshine; and all the countless material things
made by hands, conceived by brains.
Here it is, all about us : evidence that the drive behind life
has lost none of its power; proof that, impelled by that
drive, man can build as well as destroy ; that in his nature is
more of Vishnu the Creator than of Siva the Destroyer.
And this human culture that is ours by inheritance and by
the efforts of the generation now living, is real. It makes up
the social and much of the physical environment into which
children are to-day being born. They are the same children,
they bring with them the same old organic needs and hungers.
How will they fare?
A.D. 2000 seems a long way off; it is no more remote than
1850. My father, now living, was a young man in 1850;
my grandson, now living, may expect to be alive in 2000.
How free will the next generation be to work out its own sal-
vation, to guide its life in the light of wisdom? Will life be
more free seventy-five years hence than it is to-day? Are
we more free than were our ancestors two thousand years
ago?
How free are we of to-day — ^from war, pestilence, earth-
quake, volcano, fire, sickness, idiocy, imbecility, pauperism,
crime, squalor, shipwreck, stupidity, ignorance, superstition,
479
i
WHY WE BEHAVE LIKE HUMAN BEINGS
famine, disease; from accidents of mines, factories, railroads,
automobiles, and airplanes ; from harsh sounds, bad air, and
foul odors; from scorn, malice, and intolerance; from vested
interests and established opinion in church, school, and gov-
ernment in home, society, and nation; from clocks, time-
tables, and calendars; from the decrees of fashion, the con-
victions of the mob, the mandates of the politicians? In short,
how free are we of the ox goad and the treadmill? We know
that winter will come, and provide accordingly; our expecta-
tion that there will be another harvest next year is that of the
bees and the squirrels. More free to live than we were, more
prepared to die; but in all respects more free? It is doubtful.
It is less doubtful that we are not as free as we might be.
Fast, yes: we live at an incredible speed. Experience is
disseminated and things and beings are transported across
lands and seas unknown a few centuries ago, and at a speed
inconceivable to the pioneers of the Pony Express. We can-
not yet travel as fast as sound-waves, but it is not incredible
that a future generation will travel as fast as light-waves.
In so far, then, as man has speeded living, and to the extent
that he has freed human beings, he is fulfilling his destiny.
But has he completed his mission? Has he made the most
of his opportunities? Is he progressing, is he on the straight
and shining rails, or is he in a maze, a blind alley, an appen-
dix to a cecum which holds the threat of gangrene and
destruction? There are criteria for life; is there a biologic
criterion for progress?
Note again that, while culture was inevitable because man
is a nervous, excitable, unarmored, defenceless, selfish, self-
centered, opinionated, inquisitive, bullying, cowardly, talk-
ing, marrying animal, wko requires shelter, food, and a mixed
diet, and has a big head and quick wits and is handy with
his hands, the particular bents culture took were no more
inevitable than are the particular words I am now putting
down on paper. If Buddha and Confucius, Moses and Plato,
480
FROM THE STANDPOINT OF THE NEWER PSYCHOLOGY
Washington and Lincoln, "svere inevitable, then I can tliink of
nothing less illuminating as a guide to human conduct than
human histor}*. If not inevitable, then tliey are priceless
illustrations of man's capacity to transcend a nature which is
generally satisfied with a few simple reactions to a stimulating
world to meet a few fundamental organic needs and hungers.
Note, too, that history does not repeat itself. "Wliy should
it? ^lio wants it to repeat? To the best of our knowledge,
notliing on diis planet repeats. 'Wliile die elements and the
energies change not at all, or imperceptibly, tlie forms matter
takes and tlie work energv* performs do change. The organic
needs and hungers inliere; diey drive man to-day, as yester-
day, as in pre-Cambrian days, diey drove his ancestors.
Drove? How? By a stepping up, a raising of die potential
of the power. As a result, the machine became more com-
plicated but more highly integrated; its parts became larger
but under better control; it was capable of more refined
work, could vary its output, forecast die future, provide for
unforeseen contingencies. This is creative evolution. It is
real, it is tangible, its history can be read in the rock record,
can be measured in the cortex of die brain, and can be seen
in the fields of waving grain and in the flocks of sheep and
the herds of cattle. It was in the direction of freedom.
WhsLt is freedom? No two dictionaries define it alike. No
two generations define it alike. No one generation agrees as
to who shall be free. The framers of our Magna Charta of
freedom went right on killing Indians and breeding slaves.
W^e shall get little insight into freedom from die law courts;
we must look deeper. Can we find a biologic concept for
freedom? Is there a goa/, as it were, to creative evolution?
Our vision is so limited! We know so little of life! "^lio
shall say?
But we shall trv*. All die cats, dogs, rats, and guinea-pigs
martvTed in the name of science have died in vain, and all the
laboratories built to serve science are illusions, if the net
result is but a few human lives saved and no light thrown
4^1
WHY WE BEHAVE LIKE HUMAN BEINGS
on what it is that is saved and whether it is wcyrth savings
Life can save itself if given a fair chance. What is worth
saving? What is the direction of creative evolution? What
is it that has been thrown up by ages-long stirrings of the
mud? W^at quality characterizes man as it does no other
animal, his Primate ancestors as it does no other order of
mammals ; which distinguishes a fertilized human ovum from
all other protoplasm ; which furnishes us a key to human cul-
ture, reduces our What-has-evolved to a lowest common de-
nominator, and gives us a clue to the freedom that is the
goal of creative evolution? The capacity to modify and delay
reactions according to experience. That kind of behavior is
called intelligent.
Intelligence is vague; we must give it reality. It means
to learn. But every animal learns — ameba, oyster, fish,
groundhog. The squirrel stores nuts for a wintry day. The
instinctive behavior of many animals is remarkable. But we
can speak of the evolution of intelligent behavior. And that
is no mere figure of speech. Nor is it without significance
that with man, and with man only, we find human intelligence.
Of all Primate infants, the human infant alone learns human
behavior.
Wliy? Because it has a larger learning equipment, more
ways of obeying impulses, a greater capacity to modify im-
pulses in the light of experience.
Tap my patellar ligament, my foot kicks out; but only after
a lapse of time. The interval was short, but time was re-
quired for spinal cord to deliver the impulse after spinal
cord had received news of the tap. But tap me on the head :
I may think that over for fifty years before I thank you and
admit that you were quite justified, and thereby end my re-
action in adjustment. Insult my child by just one word: I
may devote my life to the destruction of you and your family
and all that you hold dear. Some rulers have gone to war
for less. Human intelligence has taken such bents. But as
482
FROM THE STANDPOINT OF THE NEWER PSYCHOLOGY
Dr. Johnson said, "God Himself, sir, does not propose to
judge man until the end of his days." Why should we?
Man, as no other animal does, can delay his reactions
whereby he adjusts himself to circumstances; he thereby
gains a measure of control over his environment denied all
other living beings. Such control is biologic freedom, the
goal of creative evolution. Intelligence. What this control
can lead to is just beginning to be understood. Scientific in-
telligence may yet be born. Freedom is as yet only a goal
and a long way off, but progress toward freedom will speed
up; it is of the nature of living organisms to grow by what
they feed on and to climb by their own steps; the greater
freedom, the faster the pace toward the goal.
That is, if man is really on the track — and that we cannot
know. We do know that countless kinds of living organisms
dropped from sight because they were on a by-path. But
assuming that man is on the road of freedom, how can he
keep going? Is there anything in his nature which conditions
progress — as there are hormones which regulate growth?
There is something which suggests a parallel.
Why is man not as free as he might be? Because his mind
is made up; his pride of opinion outweighs his desire to
know; he dismisses realities with a "God's in His Heaven —
All's right with the world," and neglects the first lesson he
ever learned — which is, that he can learn. Because he re-
fuses the dare thrown to him by nature herself: Know thyself;
and refuses to heed the warning written across every page
of history and strewn across the face of the earth itself: the
best defense is offense, versatility rather than walls or armor-
plate, foresight rather than hindsight. Man alone can set
man free.
The human being that can learn no more has parted with the
only priceless possession in human inheritance. The men,
women, or nations that harden in their mould, get set in
their ways, crystallize their opinions and beliefs, and swear
by and live according to their routine habits— such men,
483
WHY WE BEHAVE LIKE HUMAN BEINGS
women, or nations are old; senile decay is at hand. In them
creative evolution has ceased to function. And they, in their
vain yearnings for immortality, forget how they learned to
behave like human beings and how life itself in human
beings renews its youth and speeds up the race for freedom:
As A Little Child, with an Open Mind.
484
BIBLIOGRAPHY
(The books named below do not constitute a bibliography of
man, merely the more important of the recent works consulted in
the preparation of this volume. Those to which I am especially
indebted, and from which I have drawn freely, are indicated by an
asterisk. )
^Armstrong, E. F. Enzymes, Ch. XIV, Colloidal Behavior. New
York, 1924.
Bergson, H. Creative Evolution. London, 1922.
Blumer, G. (editor) Billings-Forchheimer's Therapeusis of In-
ternal Diseases. New York, 1924.
Boas, F. The Mind of Primitive Man. New York, 1922.
BoGUE, R. H. (editor) Colloidal Behavior. New York, 1924.
Bragg, Sir William. Concerning the Nature of Things. New York,
1925.
* Cannon, W. B. Bodily Changes in Pain, Hunger, Fear and Rage.
New York, 1922.
* Carlson, A. J. The Control of Hunger in Health and Disease.
Chicago, 1916.
* "Organotherapeutics," in Billings-Forchheimer's Therapeusis
of Internal Diseases. Blumer Edition. New York, 1924.
*Chamberlin, T. C. The Origin of the Earth. Chicago, 1918.
*Child, C. M. Senescence and Rejuvenescence. Chicago, 1915.
Individuality in Organisms. Chicago, 1915.
* The Origin and Development of the Nervous System. Chicago,
1921.
Physiological Foundations of Behavior. New York, 1924.
Davenport, C. B. Heredity in Relation to Eugenics. New York,
1911.
Deniker, J. The Races of Man. New York, 1900.
*Du Bois, E. F. Basal Metabolism in Health and Disease. Philadel-
phia, 1924.
485
WHY WE BEHAVE LIKE HUMAN BEINGS
Duckworth, W. L. H. Morphology and Anthropology. Cambridge,
1915.
Edman, I. Human Traits. Boston, 1920.
Ellis, H. Man and Woman. New York, 1914.
Geddes and Thomson. Sex. New York, 1914
Haddon, a. C. The Races of Man. New York, 1925.
Harrow, B. Glands in Health and Disease. New York, 1922.
* Henderson, L. J. The Fitness of the Environment. New York,
1913.
*Herrick, C. J. An Introduction to Neurology. Philadelphia,
1922.
* Neurological Foundations of Animal Behavior. New York,
1924.
*HowELL, W. H. a Text-Book of Physiology. Philadelphia, 1922.
Jennings, H. S. Behavior of the Lower Organisms. New York,
1915.
Johnstone, J. The Mechanism of Life. London, 1921.
*Jones, F. W. Arboreal Man. London, 1916.
*JORDAN, E. O. General Bacteriology. Philadelphia, 1924.
Keane, a. H. Man Past and Present. Cambridge, 1920.
*Keibel and Mall. Human Embryology. Philadelphia, 1910-1912.
Keith, A. Man. New York, 1912.
The Engines of the Human Body. Philadelphia, 1920.
The Antiquity of Man. London, 1920.
Kendall, A. I. Civilization and the Microbe. Boston, 1923.
Kroeber, a. L. Anthropology. New York, 1923.
Loeb, J. The Organism as a Whole. New York, 1916.
Regeneration. New York, 1924.
*LuLL, R. S. Organic Evolution. New York, 1921.
The Ways of Life. New York, 1925.
MacCurdy. G. G. Human Origins. New York, 1924.
Marshall, F. H. A. Physiology of Reproduction. London, 1922.
*McCoLLUM, E. V. The Significance of Colloids in the Dietary.
Ch. XXIX, Colloidal Behavoir. New York, 1924.
McFarland, J. Biology. Philadelphia, 1920.
Metchnikoff, E. The Nature of Man. New York, 1906.
*MiLLiKAN, R. A. The Electron. Chicago, 1924.
MiNOT, C. S. The Problem of Age, Growth, and Death. New York,
1908.
486
BIBLIOGRAPHY
*MlTCHELL, P. H. General Physiology, New York, 1923.
Newman, H. H. Readings in Evolution, Genetics, and Eugenics.
Chicago, 1921
OsBORN, H. F. The Origin and Evolution of Life, New York, 1921.
Parker, G. H. Smell, Taste, and Allied Senses in the Vertebrates,
Philadelphia, 1922.
*Pearl, R. Biology of Death. Philadelphia, 1922.
Studies in Human Biology. Baltimore, 1924.
Pearson, K. The Chances of Death. London, 1897.
The Grammar of Science. London, 1900.
Robertson, T. B. Principles of Biochemistry. Philadelphia, 1924.
ScHAFER, E. A. The Endocrine Organs. London, 1916.
Thompson, D. W. Growth and Form. Cambridge, 1917.
Thomson, J. A. The System of Animate Nature. New York, 1920.
Thorndike, E. L, The Original Nature of Man. New York, 1923.
Walter, H. E. Genetics. New York, 1913.
The Human Skeleton. New York, 1918.
Washburn, M. F. The Animal Mind. New York, 1923.
* Watson, J. B. Psychology from the Standpoint of a Behaviorist.
Philadelphia, 1924.
— —Behaviorism. New York, 1925.
*Wiedersheim, R. The Structure of Man. London, 1895.
Wilder, H. H. History of the Human Body. New York, 1909.
Wilson, E. B. The Cell in Development and Heredity. New York,
1925.
487
Abel, Prof. John J., vi
on Adrenin, 210
on blood, 173
on hormones, 203
on kidneys, 186
on pituitary, 216
Abdominal viscera, 235
Abnormalities, causes of, 24
variations of, 24
Absorption, 133
Acetaldehyde, from pyruvic acid, 121
Acids, Amino-, 142, 146, 154, 156, 157,
158
butyric, 158
capric, 158
caproic, 158
caprylic, 158
hydrochloric, 146, 150
manufacture of, 185
lactic, 326, 327
nucleic, 151
oleic, 141
tri-iodo-tri-hydro-oxyindole propion-
ic, 206
uric, 221
Acidosis, 207
A cos, 203
Acquiring Human Behavior, 336-415
Acromegaly, 217
Action, osmotic, 304
reflex, 284, 308, 309
Adam's apple, 8, 134
Adaptation, 391
of human ovum, 3
Addison's disease, 239
symptoms of, 209, 210
Adenoids, growth, 134
Adiposity, 434
Adolescence, changes physical and
mental, 36
489
INDEX
Adrenal cortex, 230, 232, 238, 239
medulla, 239
Adrenalin, 210, 211, 212, 240
action of on blood vessels, 211
results from, 211, 212
Adrenals, 208, 209, 210, 215, 228
accessory, 215
location of, 202
variations in, 209
Adrenin, 210, 211, 214, 239, 368,
characteristics of, 211
Afferent, 288
African, compared with other types,
42
Agamic reproduction, 246
Agar-agar, 140
Age, changes in old, 37
Age of Fishes, Paleozoic, 63
of Mammals, Cenozoic, 63
of Man, Psychozoic, 63
of Reptiles, Mesozoic, 63
orders of, 69
of Steam, 64
Agents, immunity, development of,
204
regulating, development, 203
Agglutinin, 176
Air, complemental, 170
residual, 170
supplemental, 170
Air-sacs, work of, 124, 125
Albinos, cause of, 14
Aldrich, on adrenin, 210
Algae, one-celled, 95, 145, 465
Alimentary canal, 19, 133, 134, 405,
428
formation of, 19
lining of, 133
muscles in, 133
organs developed from, 19
serous coat, 134
INDEX
Allantois, action of, 72
Allen, on ovaries, 227
Ambergris, 152
Ameba, 78, 94, 96, 125, 189, 200, 247
269, 271, 273, 274, 275, 279, 283
334, 344, 442, 450
characteristics of, 78
Jennings on, 273
life in, 125
processes of, 450
reaction of, 334
where found, 189
Ameboid movement, of protoplasm, 78
Amenorrhea, 217
Amentia, 458
America a Family Matter, Gould, 119
Amino-acids, see Acids, amino
Ammonia, 88
Ammonium, 292
Amnion, 4, 72
Amniotic fluid, 72
Amphibians, man's inheritance from,
74
Amphioxus (lancelet), 74, 76
relation to vertebrates, 76
Amplifier, in man, 57
Amylase, 150
Anabolism, 127
Analysis, logical, 407
Ancestors, effect on race, 39
inheritance from, 112
number of, 112
Anemia, 231
Anemone, sea, skin of, 300
Anglo-Saxon, as race, 43
Animal life, geologic time-table of, 63
Animal Mind, by Washburn, 270
Animals, one-cell. Construction of, 6
constant — temperature, 179
segmented, 6
unicellular, 1
warm-blooded, 179
Animism, 96
Anthrax, bacillus of, see Bacillus,
anthrax
Anthropoids, development, 52
Anomaly, 250
Anoxemia, 175
Antediluvian ectoderm, 253
Antibodies, 149, 176, 177, 203, 249
Antigens, 176, 177
Antiricin, 198
Antitoxins, 198
Ants, fossil, 62
Apes, babies of, 56
anthropoid, kin to men, 49
similarity to men, 50
Appetite, complex, 424, 425, 426
Aorta, 164, 167, 168
branches of, 8
Apes, Anthropoid, 4
manlike {Simiidae), 49
Appendix, 21
Arabinose, 139
Archeozoic Era, 63
Arcs, reflex, 365, 366, 439
Arm, modifications of, 54
Armpits, 162
Arms, variation of muscles in, 30
Armstrong, on enzymes, 147
Aromatic amino alcohol, formula for,
210
Arsphenamin, "606," 200
Arteries, 8, 159
carotid, 8
pulmonary, 8
Arteriosclerosis, 164
Artery, construction of, 164
pulmonary, 168
Arthropods, joint-foot, 76
Asiatic cholera, cure for, 200
Association of ideas, 70
Asthma, bronchial, 212
Ataxia, Locomotor, 342
Atmosphere, composition of, 81, 87
elements of, 87
Atom, nucleus of, size, 85
smallest unit of elements, 84
Atomic number, 84
Atoxyl, 200
Atrophic cirrhosis, 152
Atrophy, 230, 239
Auricles 22, 165, 167
formation of, 22
INDEX
Australian blacks, 46
Autocoid substances, 203
Auto destruction, 179
Autonomic nervous system, 213, 214
nerves, 366
system, 324, 325
Axis, vision of, 409
Axons, 288
Babies, apes, 56
blue, 169
lemur, 56
monkey, 56
Baboons (cercopithecidae) , 49
Bacilli, tubercular, 164, 199
Bacillus, 195
anthrax, 198, 207
hay, 197
Backbone, 7
end of, 27
Bacteria, 79, 95, 130, 131, 132, 153,
162, 163, 176, 177, 186, 190, 195,
196, 197, 199, 200, 255, 256, 268, 465
chromogenic, 195
different strains of, 199
filterable, 196
forms of, 195
immunity from, how acquired, 200
in dead horse, 131
in large intestine 153
in life, 130
innoxious, 195
in one gram of soil, 131
nitrogen-fixing, 131, 132
noxious, 195
pathogenic, 195, 197
plague, how carried, 190
plants, or animals? 79
psyche of, 268
psychology, 268
saprophitic, 195
sea scavengers, 132
sulphur, 95
ultramicroscopic, 196
uses of, 79
zymogenic, 195
Bacteriology, 200
Bacterium, 158, 163
Bacteremia, 198
Banting, isolation of insulin, 219
Barker, on hormones, 203
Basal metabolism, rate of, 397
Bayers "205," 199
Bechold, on enzymes, 147
on liver cells, 152
Behavior, bisexual, 430, 431
changes in, 469
fashionable, 473
human, and environmental, 469
standard of, 470
instinctive, 341, 417
intelligent, 482
marriage, 441, 442
socially useful, 471
society, 469
somatic, 416
unsocial, 473, 476
unverbalized, 370, 372
useful, 473
Bergson, on "wits," 62
Beri-beri, 142
Bibliography, 485-487
Bile, 136, 151, 264
secretion of, 185
use of, 185
Biology, coining of word, 102
law of development, 3
Biophores, 113
Birth of earth and planets, 80
Bisexual behavior, 430, 431
Blastula, 5
Blood, aerated, 171
arterial, 167, 171, 185
circulation of, 124
clotting of, 161
composition of, 88
difference in species, 176
functioning of, 159, 160
peripheral, 182
venous, 167, 174
blood-cells, red, 177
description and work, 174
Blumenbach's scheme of races, 38,
39
INDEX
Boas, Prof. Franz, viii, 39, 45
grouping of man, 45
Body, change in proportions, 33
growth processes, 201, 202
task of, 36
Body-cells, planarian, 107
Boils, cause of, 197
Bone, sphenoid, 215
Bones, episternal, 26
facial, 34
frontal, 28
growth of, 34
nasal, 28
skull-dome, 34
upper arm, formation of, 27
Brain, 10, 11, 12, 32, 33, 37, 42, 58,
65, 70, 237, 280, 295, 297, 298, 305,
310, 316, 319, 329, 458
cells of, 10
correlation with hand, 70
cortex, 280, 297, 298, 305, 319, 458
distinguishing features of man's, 70
formation of, 10
Herrick on the, 329
loss of weight with age, 37
microcephalous, 10
size of, 11
weight of, 11
use of, 11, 12
Mitchell on the, 316
necessity of big, 65
sizes of, 237
stem, 310
structural changes, 10
weight of, 32, 33, 42
compared to body, 58
in proportion to spinal cord, 58
Breathing, rate for adolescents, 172
rate for adults, 172
rate for children, 172
rate for newborn, 172
Breeding, rates of productivity, 98
variations in, 99
Bromine, 88
Bronchi, 169
Bufagin, 210, 211
Caisson, 172
Calcium metabolism, 207
Calorie, "great calorie," 127
Calories, 88, 128, 129, 156, 178
number expended in various occu-
pations, 128, 129
number required for growth, 128,
129
potential energy, number in, 128
produced daily by man, 88
Cambrian era, 74
Canal, alimentary, 405
Canals, semilunar, 13
Canine teeth, in apes, 71
Cannon, Prof. Walter B., viii, 136,
213, 214, 215
on adrenals, 215
on adrenin, 213, 214
time of movements, 136
Capacity, vital, 170
Capillaries, 154, 159, 161, 162, 165
Capuchin, brain of, 52
Carbohydrates, 130, 138, 139, 156, 184
digestion of, 184
forms of, 130
specific, 139
structure of, 138
Carbon, 90, 91, 94, 130
behavior of, 91
composition of, 94
importance of, 91
necessity of, 130
relation with other elements, 91
dioxide, 72, 79, 89, 121, 124, 130,
171, 172, 173, 174, 175, 203, 214
composition of, 89
excess in blood, 124
from glucose, 121
functions of, 203
in air, 130
in blood, 72
prevalence of, 89
Cardio-vascular apparatus, 216
Carlson, Prof. A. J., viii, 206, 207,
227, 238
on endocrines, 238
on tetany, 207
on thyroid, 206
INDEX
Carnegie Laboratory of Embryology, 5
Carotid arteries, 8
Cartilage, 7
Cartilages, of larynx, 233
thyroid, 8
Casein, 150
Castle, Prof. W. E., viii
Catalyzer, 146, 220, 232, 268, 330, 331
Catalyzers, development of, 204
of development, 232
Cataract of eye, 13
Cattell, Dr. McKean, viii
Caucasian race, where found, 45
Cebidae (monkeys), 49 characteris-
tics of, 52
Cecum, 136
in herbivorous animals, 140
Celibacy, 434, 439
Cell, characteristics of, 94, 95
metabolism, 398
Cells, bone-forming growth of, 34
division of, 110
floating, 1
Leydig, 231
life in tissue, 122
occurrence, 1, 2
Cellulose, 140, 153, 195
in plants, 140
Cementum, 288
Cenozoic Age, 63
Centrosomes, behavior of, 110, 111
Cercopithecidae (baboons), 49
characteristics of, 51
Cerebellum, 310, 311, 312, 313
Cerebral cortex, 310, 318, 321, 329,
332
Cerebri, hypophysis, 215
Cerebrum, 310, 313, 314, 315, 316, 317
Gall on the, 315
Chamberlain, Foundations of Nine-
teenth Century Civilization^ 119
Chamberlin, geologist, 80, 81
Change, continuous, 92
Character, 444, 461, 472
foundations of, 472
Characters, acquired, 102
Charlatans, 462
Chaulmoogra oil, 200
Chemical receptors, 298
Chemotherapy, 200
Child, on excitation, 277
on nerves, 288
study of flatworms, 107
Children, rachitic, 143
Chimpanzee, characteristics of, 50
Chin, mental point, 28
Chlorine, 83, 137
Chlorophyl, 130
Cholelith, 152
Cholera, 231
Asiatic, cure for, 200
germs of, 197
Cholesterol, 151, 152
Chromatin, 77, 110
Chromogenic bacteria, 195
Chromophilic substance, 331, 332
Chromosomes, 110, 111, 112, 113,
behavior of. 111
inherited, 113
number of, 110, 112
Chyle, 154
Chyme, 135
Cilia, 78, 169, 269, 270, 414
in protoplasm, 78
Clairvoyants, 462
Cleft, embryonic bronchial, 206
Clefts, bronchial, 7,
gill. 7, 8
Climacteric, 228
Cloaca (sewer) in human fetus, 16, 17
Clotting, of blood, 161
Cobra, venom of, 187, 198
Coccus, 195
Coccyx, tail skeleton, 27
Cod, eggs of, 98
Collip, on parathyroids, 208
Colloids, development of, 94
Color, biological significance of, 40
in different races, 46, 47
Complex appetite, 424, 425, 426
hunger, 425, 426
libido, 427
reproduction, 428
Compounds, organic, 137
number of, 91
493
INDEX
Comte, on biology, 237
Conditioning of reflex arc8, 379, 385
Conduct, normal, 470
Conjugation, of individuals, 105
Connective tissue, 6
from thymus, 208
Consciousness, 314
critical, 476
Contents, xi-xiv
Corals, 75
Cord, spinal, 310
umbilical, 168
Cornea, 13
Corpus luteum, 226, 228
Cortex, 209, 238, 239, 280, 282, 289,
297, 298, 305, 312, 316, 317, 318,
319, 321, 329, 332, 362, 402, 426,
458
adrenal, 238, 239
brain, 280, 297, 298, 305, 319, 458
cerebral, 310, 318, 321, 329, 332
effect of removal, 209
functions of, 209
Herrick on, 318
Woods Jones on, 316
Coughing, effect of, 134
Cramps, 325, 326, 327
Cranial, 213
nerve, 8
nerves, 310
Crests, iliac, 235, 236
Cretinism, 238, 239
Cretins, 205
Croup, 199
Cro-Magnon man, characteristics of,
48
Crustacea, pre-Cambrian, 62
Cryptorchic individuals, 230
Crystalline, 156
Crystalloids, in solution, 94
Crystal, hemoglobin, 176
Crystals, growth of, 95
Culture, development of, 479
Curare, 327
Current, electrochemical, 148
Cyanosis, 169, 174
Cynocephalous (baboon), character-
istics of, 51
Cynodont, 71
Cysts, dermoid, 25
cause of, 25
Cytoplasm, mass of, 288
Darwin, 13, 97, 98, 99, 104, 113
"gemmules," 113
origin of species, 104
Darwin's point, 13
Davenport, 102, 114, 117, 118
investigations in Jukes case, 117,
118
on atavistic characters, 114
Death, causes of, 254
natural, 37, 38
man's consciousness of, 478
Pearl on, 252, 254
rate, 253
decline of, 260
Decrement, 283
Degeneracy, in food canal, 21
Delage, experiments in fertilization,
108
Delirium tremens, 231
Dementia, 458
praecox, 221
Dendrites, 331
Dendrons, 288, 289
Dental germs, ridges and cross ridges,
20
Dentine, 288
Dentition, adaptations of, 19
permanent, 36
Derbyshire neck, 205
Dermis, 14
Descartes, on pineal, 218
Detumescence, process of, 432
De Vries, mutants, 101
mutation theory, 100
Development of diurnal habits, 399
Devonian Period, 73
Dextrin, 150
Dextrose, 139-151
Diabetes, 216, 217, 219, 220, 300
insipidus, 216, 217
mellitus, 216
Dialysis, 155
Diffusion, 155
INDEX
Digesters, parasitic, 141
Digestion, 133, 136, 141, 146, 155
and heat, 136
chemistry of, 146
mechanics of, 146
organs of, 136
process of, 133, 134
Digestive organ, 414
system, 133
Digitalis, 210
Di-hydroxymethyl-aminoethylol ben-
zine, 210
Diphtheria, 199, 200, 256
immunity from, 200
Disaccharides, composition of, 139
Disease, Addison's, 239
Graves', 205
Diseases, rat- flea-borne, 187
Diurnal habits, development of, 399
Division, direct, 110
mitotic, 110
Dogma of Evolution^ L. T. More, 101
Doisy, on ovaries, 227
Donkey, heart-beats of, 166
Dreams, 400, 401, 402, 403
Drive, emotional, 478
emotional, forces of, 475
Dropsy, 161, 210
remedies for, 210
Dryopithecus, branches of, 57
Du Bois, on fats, 141
on heat, 183
on skin, 182
Dubois, 48
Duct, excretory, 231
seminiferous, 18
Dwarfs, cause of, 34
true, 47
Dwight, Thomas, vi
Dynamics, Visceral, 352
Dysentary, amebic, cure for, 200
Dystrophia adiposogenitalis, 217
Eagle, structure more specialized than
man, 62
Ear, external, cartilege of, 7
formation of, 12, 13
inner bones of, 7
Ear, lobe of, 13
muscles of, 13
Eardrum, 13
Earth, core of, 81
formation and growth of, 81
organic deposits of, 79, 80
origin of, 81
Earthworms, organization of, 76
East, Mankind at the Crossroads, 119
Eccles, on parasites, 186
Ectoderm, 5, 6, 14, 253, 254
antediluvian, 253
Edema, 161
Eifector, 305
Efferent, 289
Eggs, complexity of, 72
effect of thymus on shells, 208
of reptiles, 73
personal incubation, 71
varieties and development, 72
Elements (L M N's), combinations
of, 83
four necessary, 83
number of, 85
radioactive, 85
stable, 85
transmutability of, 85
unit of, 85
Electricity, in matter, 86
Electrolytes, 83
Electron, structure of, 86
Electrons, behavior of, 470
negative, 84
positive, 84
Elephant, breeding rate, 98
heart-beats of, 166
elephantiasis, 161, 162
Elixirs, 241, 255
Ellis on erogenous zones, 395
Embryonic bronchial cleft, 206
Embryo, abnormal development of, 25
cells of, 3
development of, 4, 8
food of, 4
growth of, 6
human, adrenal in, 209
at bronchial-cleft stage, 21
nourishment of, 72
INDEX
Embryo, stages of development, 5
blastula, 5
gastrula, 5
morula, 5
Emotional organization, 378
qualities, McDougall on, 418
reinforcement, 358
Emotions, 362
End receptors, 288
Endemic goiter, 205
Endocrine, 239
gland, 14, 204, 214, 220, 227, 251,
262
development of, 204
Endocrine Glands and the Causes of
Death, 201—262
Endocrines, 202, 206, 219, 224, 232,
238, 240, 241
arrest of development, 240
Carlson on, 238
Keith on, 241
new science of, 219
over-stimulation of, 240
Endocrinology, 216
Endoderm, 5, 6, 254
Energy, conversion of, 125, 126
fuel for, 127
necessity of, 120
sun's, 93, 94
Enterokinase, 151
Environment, 274
fitness of, 86
Enzyme, 179
lucif erase, 268
Enzymes, 136, 146, 147, 148, 184, 185,
203, 204, 220, 331
changes in, 141
discovery of, 203
of pancreas, 136
Eocine times, use of teeth in, 71
Epidermis, 14
Epiglottis, 8, 299
Epilepsy, 221
Epinephrin, 210, 211, 216
Epiphyses, appearance of, 33
Epithelum, 206
Epithyroid gland, 19
Equilibrium, dynamic, 126
of body, 172
sense of, in ear, 13
Erepsin, 151
Ergot, 216
Erogenous zone, 432, 439, 440
Ellis on, 395
Erythrocytes, 173
Eskimo, 141
skulls of, 43
Esophagus, 134, 146, 421
passage to, 134
work of, 146
Ether-waves, 295, 296
vibrations, table of, 295
Ethyl-alcohol, 264, 301
Eugenics Society, 115
Eunuchs, 224
Eustachian tube, 8
Evans, on Vitamin x, 144
Evolution, agencies of, 99
animal, 95, 96
control of, 116
creative, 481
inorganic elements to organic com-
pounds, 82
laws of process, 104
of the Earth, Life, and Sex, 60-119
organic, 477
plant, 95, 96,
Excitation, Child on, 277
Excretion, 133
organic substances in, 88
Excretory duct, 231
Exophthalmic goiter, 205
Exteroceptors, 298, 302
Extract, thyroid, feedings of, 205
Extracts, luteal, 228
ovarian, 228
Eyeball, formation, 13
Eyes, cornea of, 13
eyeball, 13
formation of, 13
lens of, 13
"Mongolian," 14
optic nerve, 13
Primates, 70
INDEX
Eyes, retina, 13
stereoscopic effects, 70
Face, uses of, 36
Fallopian tubes, 2, 17
formation of, 17
Family, hearth of, 478
Fashion, influences of, 473
Fat-soluble A, 143
storage of, 156
Fats, 141
digestion of, 184
synthesization of, 130
Feet, proportions of, 35
Fertilization, changes during, 112
experiments in, 108
one species from another, 108
Fetal skin, 14
Fetus, 4, 17, 25, 208, 228
a parasite, 25
development of, 4
membranes of, 4
sex in, 17
thymus in, 208
Fever, dengue, germs of, 196
quartan, 192
relapsing, 196
cure for, 200
scarlet, 199
Texas, 199
typhoid, 199
typhus, 192
yelloyr, germs of, 196
Fibrin, 160, 161
Fibrinogen, 160
Finger, opposable first, 66
Fingers, extra, cause of, 24, 25
Fish, adaptations from fin of, 103
thyroid gland in, 204
Fishes, contributions to animal life, 75
man*s debt to, 74
Fishworm, form, 76
Flat feet, cause of, 33
Flatworms, 75
planarian, behavior of, 107
Flexor muscles, 30
Fluorine, uses of, 137
Fly, tsetse, 199
Follicles, Graafian, 226, 227
Food, absorption of, 154, 155
colloidal nature of, 138
effect on structure, 108
how consumed by cells, 145
in small intestine, 151
predigested, 158
travel through alimentary canal,
134, 135
Food-hunger, 466
Foods, inorganic, 137
Foot, changes in human, 27, 56
influence on civilization, 65, 66
Pithecanthropus, 56
primitive five-toed, 66
Foot-and-mouth disease, germs of, 196
Foramen ovale, 168, 169
Formaldehyde, 145
Foundations of Nineteenth Century
Civilization, Chamberlain, 119
Fovea, center ofj 409
Freedom, 481
biologic, 483
Freemartins, 225
Freud, on psychosis, 369
Freudian psychoses, 448
Freudism, 449
Freudists, 462
Frontal bone, 28
Fructose ("fruit-sugar"), 139, 146
Fuel, for body, 125
Gait, upright, changes caused by, 26
changes in acquiring, 34
Galactose, 139, 151
Gall, on cerebrum, 315
on cholesterol, 151
Galton, Francis, predictions of, 117
Gambetta, size of brain, 11
Gametic reproduction, 246
Ganglia, 324, 418
Gastric juice, 135, 221, 426, 427
tetanus, 351
Gastrula, 5
Geddes (quoted), 105
Geikie, 80
Gels, 160
INDEX
Gemmules, 113
Genealogic time-table, 60
Genetic behavior, 267
history, 416
Genus Homo^ 204, 264
Germ-cell, fertilized ovum, 2
Germ-cells, 3, 107
Germ-layers, ectoderm, 5, 6
endoderm, 5, 6
mesoderm, 5, 6
Germ-plasm, theory of continuity, 117
Germs, disease-producing, 193
malaria, quinine for, 200
Gibbon, {Hylobates), characteristics
of, 51, 52, 53
fingers of, 66
hand of, 66,
young of, 68
Gill-arch, 7, 206
Gill-clefts, 7
Girdle, pelvic, 26, 233, 235
Gland, endocrine, 185, 204, 220, 227
lachrymal, 286
pineal, 218
pituitary, 215
Glands, adrenal, 213
behavior under operations, 202
duct, 185
functions of, 201
endocrine, see Endocrine glands
epithyroid, 19
exocrine, 185
female, changes in, 17
food-digestion, 184, 185
functions of different, 15, 16
gastric, 184
hormonopoietic, 203
lachrymal, 14, 184
male, 17
migration of, 17
mammary, 16, 224, 228
milk, 16
odoriferous, 15
of stomach, 135
pituitary, 19
salivary, 134, 320, 321
sebaceous, 15, 184
secretions of, 185
Glands, sex, 208, 244
function of, 202
supernumerary, 16
sweat, 15
thymus, 19
use of, 184
thyroid, 19
Glandular system, 346
Globin, 175
Glottis, 415
Glucose, 139, 146, 150, 156, 220
chemical changes in, 121
formula, 90
formation of, 121
in liver, 136
solar energy in, 90
Glycerin, 141, 154
Glycerol, 154
Glycogen, 140, 156, 259
conversion to glucose, 121
in liver, 136
in muscles, 123
Goiter, 205, 231
endemic, 205
exophthalmic, 205
toxic, 205, 239
Golden rule, practice of, 470
Gonad hormones, regulators of sex
characters, 232
operations, 222, 238
Gonadectomy, 230
Gonads, 221, 224, 226
absence of, 230
characteristics of male and female,
18
development of, 18
male, 229
transplantation of, 231
Gonorrhea, 199
Gorilla, characteristics of, 50
Gould, America a Family Matter, 119
Graafian follicles, 226, 227
maturity of, 2
Grant, The Passing of the Great Race,
119
Granulobacillus saccharo - butyricus
mobilis non-liquefaciens^ 194
498
INDEX
Grape-sugar, 139
Graves' disease, 205
Grimaldi man, 48
Groins, 162
Growth, and life, 78
forces of, 122
power, at birth, 32
Guanidin, actions of, 207
Habit, inherited, 341, 343
Habits, 388, 389
breaking of, 393, 394
Hair, growth of, 15
index of type, 41
variations in, 43
Hairy Ainu, 15
Hand, fetal, 67
influence on civilization, 65
utility of, 54
Hands, development of, 55
of Primates, 66, 67
Hapalidae (marmosets), 49
Hate, 431, 432
Head, movements of, 35, 36
Heart, at branchial-cleft stage, 21, 22
beating of, 165
changes with age, 37, 38
construction of, 124
variations in structure, 22
Heat, a form of energy, 177
Heidelberg man, 48, 57
Height, 33
Hematin, 175, 176
crystallization of, 176
Hemin, amount of, 177
Hemocyanin, copper of, 171
Hemoglobin, 173, 174, 175
iron of, 171
Hemolytic, 176
Hemophilia, 161
Hemorrhages, use of adrenin in, 211
Henderson, fitness of environment,
86, 87
(quoted), 89
Heredity, and energy, 93
questions of, 112, 113
Hermaphrodite, true, 76
Hermaphrodites ( Hermes- Aphrodite ) ,
cause of, 18
in plants and lower animals, 18
Hernia, cause of, 17
Herrick, Prof. C. Judson, viii, 273,
318, 329, 373
on brains, 329
on psychology, 273
on the cortex, 318
Hertzian waves, 296, 298, 306
Hexapoda, 188
Hirudin, 161
Homing instinct, 337
Hominidae (men), 49
Homo, from apes, 57
Homo (genus) Sapiens (species),
44, 264
Hookworm, 188
Hormone, 17, 208, 216, 220, 224
and sex, 17
structure acted on, 17
pineal, 218
production of, 227
secretion system of, 384
thyroid, 205
Hormones, 203, 204, 221, 225, 226,
232, 239, 240, 265, 450
discovery of, 203
gonad, 232
of growth, 204
production of, 221, 239
sex, 226
thyroid, 225
Hoskins, Prof. R. G., viii, 206
on thyroid, 206
Howell, on enzymes, 149
on heat, 182
Hrdlicka, 58
Human Anatomy, Quain, v
Human Embryology, Keibel and
Mall, V
Human Embryology, Minot, v
Human morphology, 416
physiology, 416
Humerus, at 15 years, 33
free, 67
Hunger, 421, 422, 423, 424, 425, 426
complex, 426, 428
INDEX
Huxley, 43
on protoplasm, 78
Hydrogen, atomic number of, 84
importance of, 91
molecular behavior, 93
Hydrolysis, changes during, 147
Hydrophobia, germs of, 196
Hypophysis cerebri, 215
Hydrosphere, 81, 82,
Hyoid apparatus, 7
Hypothyroidism, 206
Icthyosis hysterix, 181
Iguanadon, 67
Iliac crests, 235, 236
Iiuinunity agents, development of, 204
Immunology, 200
Impotence, 238
Impulses, in human beings, force of,
475
sensory, 315
Incisors, 36
Incubator, vade mecum, 73
India, sacred cattle of, 141
Indians, American, non immune, 199
Individual Life Cycle and the Human
Race, The, 1—59
Infancy, biologic significance of, 372
Infantile tetany, 207
Infantilism, 238
sexual, 217, 239
Influenza, 199
germs of, 196
Inguinal canals, cause of hernia, 17
Insanity, 317
Insomnia, 396, 397
Insulin, 219, 240
Integrating Organ and Mechanism of
Adjustment, The, 263—335
Intelligence, 454
Intermaxillaries, in fetal life, 28
Interoceptors, 298
Interstitial cells of Leydig, 229
Intestinal juice, 135
Intestine, large, size of, 136
small, 135
lining of, 135
Intestines, work of, 146
Intrauterine life, 226
Invertase, 151
Invertebrates, 7
legs of, 67
Iodine, 88
use of, 206
Ions, formation, 88
Ipecacuanha, 200
Iris, 221
Iron, 88, 137
Is America Safe for Democracy?
McDougall, 119
Islands of Langerhans, 219
Itch, laryngeal, 383
Jacobson's organ, 12
James, William, on subtypes, 45
Jaundice, 300
Jaw, lower, 7
Jaws, changes in, 28
prognathic, 28
Jellyfish, 75
Jennings, on ameba, 273
Johnson, Dr., quoted, 483
Joint, mid-tarsal, 35
Jones, Woods, on cortex, 316
on evolution, 69
Jordon, bacteria in one gram of soil,
13
on bacteria, 176, 195
on tuberculosis, 193
Juice, gastric, 220
lack of, 214
pancreatic, lack of, 214
Jukes case, 117, 118
Jupiter, origin, 81
Kangaroo, feet of, 66
Kaola, foot development of, 66
Katabolism, 127, 399
Kawakami, 143
Keith, on endocrines, 241
Kendall, isolation of thyroxin, 205
Kidneys, 18, 185, 221
function of, 18, 185
true, description of, 18
INDEX
Kidneys, types of, 18
head kidney, 18
true kidneys, 18
Wolffian body, 18
Kinesthetic organization, 340, 348, 371,
378
sense, 302, 349, 405
Koch, on theory of disease, 194
Kroeber, grouping of man, 45
L M N's, of nature, 83
Lachrymal glands, 14, 286
Lactase, 151
Lacteals, 154, 155
Lactic acid, 326, 327
from glucose, 121
from muscles, 123
Lactose, 139
Lamarck, (quoted), 97, 102
Lancelet (amphioxus) , 74
Langerhans, Islands of, 219
Language, learning of, 375
Lanolin, 152
Lanugo (down), 15
Laryngeal itch, 383
Larynx, 20, 57, 299, 233, 237
change at puberty, 233
human, 20, 57
removal of, 377
Lavoisier, vii, 219
Leeuwenhoek, discoverer of bacteria,
194
Legs, of invertebrates, 67
of joint-foot arthropods, 76
of vertebrates, 67
variation of muscles in, 30
Lemur, babies of, 56
fingers of, 66
Lemuridae (lemurs), 49
Lemurs {Lemuridae), 49
hand of, 66
type, 52
Lens, of eye, 13
Leprosy, bacillus of, 198
cure for, 200
Leptospira icteroides, 196
Lesions, pyorrhea, 189
Leukocytes, 163, 193
Lever, second order, 35
Levulose, 151
Leydig cells, 230, 231, 232
interstitial cells of, 229
Libido, 449, 450, 451
complex, 427
Lichenin, 140
Life, 58, 78, 79, 97, 98, 226, 464, 465,
466, 477, 479, 480
adult, beginning of, 58
agencies of, 477
freedom of, 479, 480
in protoplasm, 78
intellectual, 472
intrauterine, 226
prodigality of, 97, 98
span, Karl Pearson on, 255
speed of, 480
tests of, 79
Ligament, 342
patellar, 341
Ligaments, 311, 347, 349
Light, as oxidizing agent, 144
Loeb on, 293
Watson on, 293
Limb, type of first Primate's, 67
Lincoln, life of, 474
Ling, eggs of, 98
Lipase, 150
Lipoids, 141
Lips, formation of, 25
hare-lipped, 25
Lithium, 292
Lithosphere, 81, 82
Liver, 19, 21, 136, 184, 185, 202
functions of, 136, 202
variations, 21
work of, 185
Lockjaw, 207
Locomotor ataxia, 342
Loeb, experiments in fertilization, 108
on light, 293
shapes of living beings and crystals,
95
Logical analysis, 407
Longevity, cases of, 37
Love, detumescence of, 432
Watson on, 433
INDEX
Lucif erase, 399
enzyme, 268
Lull, Prof. Richard Swan, viii, 63, 77,
101
on Darwin, 101
Lull, Richard Swan, Organic Evolu-
tion, 63
Lunar cycle, effect of thyroid on, 206
Lung, azygos lobe, 21
right and left, 19
Lungs, air sacs of, 214
description of, 169
dried, 221
lobes of, 21
Luteal extracts, 228
Luteum, corpus, 226, 228
Lymph, 161, 163, 221, 250
Lymphatics, 159, 161, 162
Lymph-nodes, 162, 163
Lysin, 176
Macaques, species of, 51, 52
MacCurdy, Prof. George Grant, viii
Machnow, Russian giant, 201
Magnesium, 137
Malaria, 187
germs, death for, 200
Maltase, 150, 151
Maltose, 139, 151
Mammae, 16, 72, 229
formation of, 16
functions of, 16
secretions of, 16
Mammals, Oligocene, 69
Mammary glands, 224, 228
Man, culture of, 479
mobility in, 67
prehistoric, 59
Mankind at the Crossroads, East, 119
Marmosets (Hapalidae) y 49
fingers of, 66
Marriage, 441, 442
Mars, origin of, 81
Marshall, on fertilization, 108
Marsupial, pouch, 68
Masochist, 451
Mastication mechanism, 274
Mastigophora, 189
Mastoid processes, 36
Mate-hunger, 430, 444, 446
Maturation of sperm and ovum. 111
Maturity, sex, 232, 233
McCoUum, on enzymes, 148
on formaldehyde, 145
on predigested food, 158
McDougall, Is America Safe for De-
mocracy?, 119
on emotional qualities, 418
McLeod, isolation of insulin, 219
Measles, 199
germs of, 196
Mechanism, mastication, 274
sensori-motor, 373, 378, 428
variations in, 61
vocal, 374
Mechanisms, emotional-drive, 477
keep-in-touch, 6
Medulla, 209, 210, 213, 239, 310, 311
adrenal, 239
secretions of, 213
Melanosis, 41
Membrane, fetal, 4
nasal mucous, 221
nicitating, 14
Memory, 385, 386
Men (Hominidae) , 49
heart beats of, 166
Mendel, Gregor, cult of, 114
Mendelian characters, determination
of, 204
factors, new, 115
Mendel's "law," 114
bases of, 114, 115
Menopause, 2, 228
Mental states, 272
Mercaptan, 300
Mercury, origin of, 81
Mesentery, 21, 134, 162
arrangement of, 21
Mesoderm, 5, 6, 14, 254
Mesozoic Age, 63
Metabolism, 127, 128, 205, 207, 218,
244, 251, 270, 275, 276, 330, 331,
397, 398, 430
basal, 128
calcium, 207
INDEX
Metabolism, cell, 398
neuron, 331
processes of, 430
rate of basal, 397
sugar, 218
Metazoa, 1, 76, 106, 186, 257
ova and sperma, 106
(subkingdom II), 76
Metazoon, 257
Method of thinking, 382, 383, 384
Methylguanidin, 207
Micrococci, 195
Micro-organisms, assistance of, 141
cause of higher forms of life, 80
Milk-glands (mammae), 16, 72
Millikan, composition of atoms, 84
determination of elements, 85
(quoted), 97
Misfits, disappearance of, 470
Mitchell, on the Brain, 316
Molars, 36
four-cusped, 71
third, 36
Molecule, smallest, weight of, 93
Molecules, behavior of, 93
disaccharides, 147
monosaccharide, 147
Molluscs, forms of, 76
Mongoloid race, 45
type, color, 46
Monkeys (Cebidae), 49, 54, 55, 56
babies of, 56
hands of, 54, 55
Monosaccharides, composition of, 139
Monotremes, 72
Monsters, artificially produced, 23
variations of, 23, 24
Moore, Dr. C. R., viii
More, L. T., Dogma of Evolution, 101
Moron, definition, 458
Morons, 458, 459, 460
Morphology, 267
human, 416
Morula, 5
Mosquito, Anopheles, method of pro-
duction, 191
Motor areas, 316
mechanism, characteristics of, 123
man and oyster, 61
Mouse, heartbeats of, 166
Mouth, 6
variations in, 22
Movements, peristaltic, 136
rhythmic, 136
Mucin, 150
Mucus, 169
coat of, 153
Muellerian ducts, 17
Muscle, biceps, of Gibbon, 54
palmar, 31
pyramidal is, 30
quadriceps femoris, 342
risorius, 30
skin, 29
sphincter, of stomach, 135
variations, in facial, 30
visceral, 361
Muscles, 347, 349
calf, 35
composition of, 123
facial, comparison animal and
man, 29
flexor, 30
groups of, 123
jaw, 36
mastication, 36
number of, 29
of alimentary canal, 133
of stomach, 135
rectus abdominus, 30
serous, 134
skeletal, 214, 361, 436
sternalis, 30
trained, efficiency of, 129
Mystics, 462
Myxedema, 205, 238, 239
Nails, finger and toe, 15
Nasal mucous membrane, 221
Natural Selection, 99
effects of on race, 119
Nature, experiments of, 65
of things, 83
Navel, 4
INDEX
Neanderthal man, 48
Neck, 162
Negritos (see Pygmies)
where found, 45
Negro, characteristics of, 39, 40, 41
Negroid division, where found, 44, 45
Nephritis, 221
Neptune, origin, 81
Nerve, optic, 294, 295, 296
sciatic, 289
sensory, 307
system, Watson on, 333
Nerves, 288
autonomic, 366
Child on, 288
cranial, 310
sensory, 303
sweat-gland, work of, 182
vasomotor, 234
Nervous system, mechanism of, 9, 10
peripheral, 323
structural development of, 10
Neuritis, 288
Neurofibrils, 331
Neuromotor system, 207
Neuron, 289, 319
metabolism, 331
Neurons, 288, 307, 311, 312, 343
knots of, 324, 418
Neuroses, 234, 450
New Decalogue of Science, The,
Wiggam, 119
Newborn, heartbeats of, 166
Nitrification, process of, 131
Nitrogen, 172, 175
per cent in body, 131
protein, 157
Nitrogenous salts, 79
Nitroglycerin, 141
Nordics, supremacy of, 43
Nose, development of, 12
use of. 411, 412
Notochord, 7
in human embryo, 74
Noxious stimulus, 346
Nuclease, 151
Nuclei, 173
Nucleins, 220
Nucleoproteins, 151
Nursery, development of, 68
Nucleus {nuXy nut), 77, 110
Odoriferous glands, 15, 16
Olfactory nerves, 12
receptor, 300
Oligocene times, mammals in, 69
Oocytes, 111
Operations, gonad, 222, 238
Opsonin, 163, 176
Optic nerve, 13, 294, 295
Orang-utan {Simla satyrus), charac-
teristics of, 50
Organic Evolution, Richard Swan
Lull, 63
Organization, emotional, 378
kinesthetic, 340, 348, 371, 378
sensori-motor, 273
vasomotor, 457
Organs, sensory, 318
Osborne, 58, 69, 79, 100
Osier, on arteries, 251
Oslund, on vasectomy, 231
Osmosis, 155
Osmotic action, 304
Ossification, centers of, in bones, 33
Outline of History, H. G. Wells, 40
Ova, 226
female germ-cell, 2
sources of, 227
Ovarian extracts, 228
Ovaries, 221, 225, 229
Over-specialization, in nature, 62
Ovum, 2, 4, 5, 9, 111, 208, 229, 247,
266, 431
behavior of, 111
changes in, 111
development of, 2
discovery of, 2
division of, 4, 5
fertilization of, 2
human, 208
maturity of, 2
nourishment of, 9
number of, 2
Oxidation, changes of, 120, 121
INDEX
Oxidations, biologic, 156
Oxide, formation of, 121
Oxygen, 172, 175
energy source, 90
for embryo, 72
importance of, 91
necessity of, 122
poisoning, 175
Oxyhemoglobin, 175
Oysters, productivity of, 98
Paddles, as limbs, 67
Palate, cleft, 25
formation of, 25
Paleopithecus, 57
Paleozoic Age, 63
Palm pad, 31
Palmistry, 31
Palmists, 461
Pancreas, 19, 136, 151, 184, 202, 219,
220, 221, 225, 238, 239
as regulator of sugar metabolism,
220
function of, 202
secretions of, 136
Paracasein, 150
Paralysis, infantile, germs of, 196
Paramecium, 105
productivity of, 98
Parasites, 186
Parasitism, problem of, 187
Parathyroids, 238, 239
Paresis, 342
Parotids, where found and use of,
184, 222
Parovarium, 18
Parthenogenitic volvox, 106
Parathyrin, 208
Parathyroid, where found, 202
feedings, 207
Parathyroids, 206, 207
Passing of the Great Race, The,
Grant, 119
Pasteur, Louis, founder of biology,
194
Patellar ligament, 341
Pathogenic bacteria, 195
Pearl, on death, 252, 254
Pearson, Karl, on Life Span, 255
Pelvic girdle, 26. 233, 235
Pelvis, shape of, 236
Pepsin, 135, 150, 151, 177
Pepsinogen, zymogen of pepsin, 148
Peripheral nervous system, 323
organ, 281
Peristaltic movement, 135
Peroxidase, 149
Personality, 463, 464
Perverts, sexual, 444
Phagocytes, 163, 164, 177, 251
Pharynx, construction of, 134
Phosphorus, 137
Photograph, 130
Photosynthesize, 130
Phrenologists, 461
Phrenology, 452
Physiology, human, 416
Pigment, effect on skin, 41
respiratory, 173
Piltdown man, 48, 57
Pimples, cause of, 197
Pineal, 239
gland, 218
harmone, 218
where found, 202
Pithecanthropus erectus, characteris-
tics of, 48, 49, 57
Pituitary, 19, 217, 218, 228, 230, 238,
239
gland, 19, 215
where found, 202
Pituitrin, 216, 240
Placenta, 4, 73, 229
development of, 73
Planetary system, 80
Planets, terrestrial.
Earth, 81
Mars, 81
Mercury, 81
Venus, 81
Plants, synthesization of sugars and
fats, 130
Plasma, 160, 161, 163, 173
Plasmodium, life cycle of, 191
Platelets, 161
INDEX
Play, 353, 354
Plica semilunaris, 14
Pneumonia, 198, 199
Polyps, 75
Polysaccharides, composition of, 139
Potassium, 137
chlorides, 292
Precipitin, 176
Precocity, sexual, 238
Prejudice, racial, 119
Premolars, 36
Primate, center of evolution of, 58
evolution of, 62
man's ancestral, 71
Primates, development of, 53, 479
families of, 49
Primordial protoplasm, 419
Processes, mastoid, 36
Processes of Living and the Germs
of Disease, The, 120—200
Progress, causes of, 476
speeding up of, 64
Propaganda, for right living, 474, 475
Proprioceptors, 298, 302
Prostitution, 439
Protein, 175, 273
built from, 142
where found, 141
Proteins, 131, 132, 141, 146, 156, 184
digestion of, 184
elements of, 131
produced by plants, 132
Proteoclast, 150
Proterozoic era, 63
Protoplasm, 1, 77, 86, 157, 158, 243,
245, 246, 247, 261, 266, 269, 273,
275, 276, 283, 287, 289, 330, 331,
344, 417, 455, 465, 468
carbon in, 91
characteristics of, 77, 78
composition of, 78
functions of, 77, 78
primordial, 419
reaction of, 9
Protozoa, 1, 140, 186, 189, 257, 269,
283
Sarcodina, 189
(Subkingdom I), 76
Protozoon, 4, 75, 247
Psyche, 263, 270, 333
Psychic behavior, viii
reflex, 320
Psychics, 420
Psycho-analysis, 268, 370
Psycho-analyst, 461
Psychology, 263, 267, 273, 416, 452
Herrick on, 273
human, 416
Psychoses, 448, 450
Freudian, 448
Psychosis, 447
Freud on, 369
Psychozoic Age, 63
Ptyalin, 150
Puberty, 2, 224, 228, 232, 233, 252.
253, 439, 442
development of glands in, 16
in cretins, 205
thymus at, 208
Pubes, 233
Pulmonary artery, 8
Pulse, rate with age, 37, 38
Pygmies, stature of, 46, 47
Pygmy, pure race, 44
Pylorus, opening of, 135
Pyramidalis, 30
Pyruvic acid, from lactic, 121
Quadriceps femoris muscle, 342
Quadruplets, frequency of, 22
Quotidian, 191
Rabbit, heartbeats of, 166
Race, determination of, 38 39
Mongoloid, 44, 45
Negroid, 44
subtypes, 45
Alpine, 45
Hindu, 45
Mediterranean, 45
Nordic, 45
Rate of basal metabolism, 397
Ratiocination, 407
Reaction, biologic, 360
somatic, 299
visceral, 299
INDEX
Receptor, 312
of stimuli, 279
olfactory, 300
Receptors, 306
chemical, 298
somatic, 298
visceral, 298
Rectus abdominus, 30
Reflex action, 308, 309
acts, 396
arc, 280
arcs, 365, 366, 439
conditioning of, 379, 385
center, 281
psychic, 320
Regulating agents, development of,
203
Reinforcement, emotional, 358
Rejuvenescence, 222, 244, 247
Rennin, 150
Reproduction, agamic, 246
bisexual, 109
complex, 428
gametic, 246
necessity of thyroid in, 206
sexual, 430
Reptiles, development of, 73
giant, 71
Resonators, laryngeal pouch, in Pri-
mates, 57
Response, 356
Retina, 13, 221
Rhodopsin, 412
Ribs, first, 7
floating, 26
number and arrangement, 26
Ricin, 198
Riddle, on thymus, 208
Sacral, 213
Sacrum, 235, 236
formation of, 26
Sadism, 420
Sadist, 451
Saliva, 134
lack of, 214
Salivary glands, 320, 321
Salt, nature of, 83
strychnine, 207
Salts, mineral, 136
Saprophitic bacteria, 195
Sarcinas, 195
Saturn, origin, 81
Scaphoid bone, 67
School, demands of, 474
Schools, functions of, 472, 473
Schultz, Dr. Adolph H., viii
Sciatic nerve, 289
Scottish Brothers, 24
Scrotum, formation of in fetus, 17
Scurvy, 142, 231
Sea anemone, skin of, 300
Sebaceous glands, 15
Secretin, 151
Secretion, system of hormone, 384
Seidell, on antineuritic properties, 144
Self-control, 360
Self-preservation, 360, 466
Seminiferous duct, 18
Sensations, 454
Sense, kinesthetic, 302, 349, 405
Sensori-motor mechanism, 873, 378,
428
organization, 273
Sensory areas, 316
impulses, 315
nerve, 307
nerves, 303
organs, 318
Sensuality, 451
Sentimentality, 451
Septicemia, 198
Sera, cell-dissolving, 177
Serum, anti-bacterial, 200
antitoxic, 200
Sex, beginnings of, in protozoa, 105
differences, 106
in birds, 106
glands, 244
hormones, 226
infantilism, 239
maturity, 232, 233
Sex-complex, 431, 438, 441, 446, 451
Sex-hunger, 466
INDEX
Sex-impulse, 448
Sex-psychoses, 439
Sex-transformation, 234
Sexual characters, secondary, 58
differences, in man and in ani-
mals, 58
infantilism, 217
perverts, 444
precocity, 238
reproduction, 430
Sight, use of, 408, 409, 410
Sigmoid curve, 26, 27
Silicon, 137, 154
Simiidae (manlike apes), 49
Siva, the Destroyer, 479
Skeletal muscles, 214, 361, 436
Skin, color determination of, 40
color of, 14
glands of, 15, 16
ridges of, 14
structure of, 14
Skull, 28
shape of, 42
Sleep, cause and function of, 397-398
Sleeping-sickness, 199
cure for, 200
in Uganda, 199
Smallpox, cure for, 200
germs of, 196
Smell, sense of, 12
Snails, pre-Cambrian, 62
Society, organized, problems of, 469,
470
Sodium, 83, 137, 292
Sodium chloride, 83
Soil, bacteria in, 131
Soma, body cells, 3
Soma-cells, 258
Somatic behavior, 267, 416
reaction, 299
receptors, 298
South Sea Islanders, 199
Species sapiens, 204
Speech, effect on man, 57
Sperm, and heredity, 109
behavior of. 111
Spermatogonia, 111, 229, 230
Spermatozoa, 177
Spermia, male germ-cell, 2
Sphenodon, 218
Sphenoid bone, 215
Spinal cord, 310
formation, 10
Spine, changes in, 34, 35, 68
qualities of, 26
Spirillum, 195
Spirochetes, 196
Spleen, 220
where found, 202
Sponges, 75
Sponsler, on cellulose, 140
Sporozoa, 96, 189, 190
Sporozoan Plasmodia, 189
"Sports," 100
Standing, use of muscles in, 35
Standpoint of the Newer Psychology,
From the, 416—487
Staphylococci, 195
Starch, forms of, 139, 140
varieties of, 140
Starches, dextrin of, 151
Starfish, 76
productivity of, 98
Starvation, subnormal temperature
accompanying, 183
Stature, changes in last million years,
57
determination of, 33
increases in from birth, 32
Steapsin, 150
Stegocephalia, origin of, 73
Steinach, on Leydig cells, 231
Sternalis muscle, 30
Sternum, 26
Stimuli, 291
fearful, 364
receptor of, 279
Stimulus from visceral organ, 399
noxious, 346
Stomach, capacity of, 135
formation of, 19
muscles of, 135
treatment of foods, 135
work of, 146
Strepto-bacteria, 195
INDEX
Streptococci, 195, 199
Structures, vestigial, 301
Strychnine, dose of, 198
Styloid process, 7
Sub-linguals, where found and use of,
184
Sub-maxillaries, where found and use
of, 184
Succus entericus, 151
Sucrose, 146
cane sugar, 139
Sugar
cane, molecular weight, 141
metabolism, 219
Sugars, three complex, 139
Sulphates, 88
Sulphur, 137
in red blood-cells, 175
Sun, offsprings of, 80
Sunstroke, 181
Suprarenals, 208, 209
Survival, methods of, 99
of the Fittest, 101
Suture, 28
closing of, effect on head, 28
Swallowing center, 134
Swamis, 462
Sweat, 180
glands, 15
number of, 180
Symmetry, bilateral, 75
Symphysis, 236
Symptoms, of emotions, 212
Synapse, 289, 290, 332
Synapses, 307, 312
resistance of, 207
Synaptic system, 290
Synthesis, of man, 132
of plants, 132
Syphilis, 198, 199, 231
cure for, 200
germ of, 196
System, autonomic, 324, 325
nervous, 213, 214
glandular, 346
lymphatic, 154
System, lymph vascular, 161
neuromotor, 207
neuromuscular, 182
of hormone secretion, 384
peripheral nervous, 323
synaptic, 290
urogenital, 209, 253
vasomotor, 170, 180, 182
visceral, 346
Tactile organ, 299
Taenia, or tapeworm, 188
Tail, signs of in man, 27
Tails, prehensile, 67
Takahashi, 143
Takamine, on Adrenin, 210
Tears, use of, 14
Teats, true, 72
Teeth, bicuspids, 19
incisors, 19
molars, 19
milk, 36
number of, in animals, 19
number of, in man, 19
use in Eocine time, 71
variation in, 19, 20
wisdom, 36
Temperature, of body, 147
Tendons, 311, 347, 349
Testes, 221
Testut, anatomist, 28
Tetanus, 207, 221
gastric, 351
Tetany, infantile, 207
Carlson on, 207
Tethelin, 215, 216
Theory, vasomotor, 397
Therapeusis of Internal Diseases,
Billings-Forchheimer, viii
Thinking, 380, 381
method of, 382, 383, 384
Watson on, 383
Thomas, Dr. W. I., viii, 475
Thomson (quoted), 102
experiment with bacteria, 132
on chromosomes, 113
on the bee, 62
Thorax, 162
INDEX
Thought, creative, and education, 474
Threadworms, 75
Thrombin, 160
Thrombosis, 161
Thumb, opposibility of, 66
Thymus gland, 19, 208, 230, 238
functions of, 208
Riddle on, 208
where found, 208
Thyroid gland, 19, 206, 222, 230, 238,
239
description of, 204
ducts, 204
effect of removal, 204, 205
hormones, 225
where found, 202
Thyroid cartileges, 8
Thyroxin, 205, 240
secretion of, 206
Tibia, 342
Time-table, genealogic, 60
geologic, 63
Tissue, 159
adipose, 156
connective, 6, 208
invasion of, 198
lymphoid, 134
Toad ointment, uses of, 210
recipe for, 210
Toes, coming and going, 27
extra, cause of, 24, 25
Tonsillitis, cures for, 221
Tonsils, 221
variation in, 20
Toxemia, 198
Toxic goiter, 205, 239
Toxin, tetanus, 198
Toxins, effects of, 182
Trachea, 169
Trachoma, germs of, 196
Tree-sloths, grasping organs of, 66
Treponema pallidum, 196
Trichina, 188
Tri-iodo-tri-hydro-oxyindole propionic
acid, 206
Triplets, frequency of, 22
Trypanosomas, 189
carriers of, 199
510
Trypsin, 150, 151
Trypsinogen, 150, 151
Tuberculosis, 234, 256
acute, 199
cures for, 221
Tumescence, 432, 433
Tumors, from notochord, 7
Twins, artificially produced, 23
cause of, 23
identical, development of, 23
how distinguished, 23
variations in, 99
occurrence of, 22
"Siamese," 24
Two-headed Nightingale, The, 24
Tympanic cavity, 8
Tympanum, 13
Types, extreme, 43
Typhoid, 198
cure for, 200
Tyrannosaurus rex, 69
Ultramicroscopic bacteria, 196
Umbilical cord, 4, 73
Ungulates, 141
Universe, social, units of, 470
Upper Carboniferous Age, 73
Uranium, atomic number, 85
atomic weight, 85
Uranus, origin, 81
Urea, 88
Uremia, 221
Uric acid, 220
Urogenital system, 209, 253
Use of nose, 411, 412
of sight, 408, 409, 410
Uterus, 216, 225, 229
action of adrenin on, 211
formation of in the fetus, 17
Variations, atavistic, 31
acquired, 100
chance, 100
continuous, 100
in systems, 19
orthogenetic, 100
predetermined, 100
progressive, 32
INDEX
Variations, range of, 31
retrogressive, 31
selected, 100
Vas deferens, 231
Vasa vasorura, 167
Vasectomy, 231
Vasomotor apparatus, 167
nerves, 234
organization, 457
theory, 397
Veins, 159
Venae cavae, 162, 165, 167
Ventricles, 165, 167
formation of, 22
Venus, origin of, 81
Vermiform appendix, 20, 21, 136
Vertebrae, cervical, 26
first, 7
lumbar, 26, 35
of negro, 41
thoracic, 26
Vertebral column, composition, 26
Vertebrates, 7
legs of, 67
sense of smell in, 69
Vestigial structures, 301
Vibrissas, 15
Villi, in small intestine, 136
Violet, Visual, 412
Viruses, 196
Viscera, 236, 303, 316, 340, 361
abdominal, 4, 21, 235
muscles of, 326
necessary in all life, 61
Visceral behavior, viii, 267
dynamics, 352
muscle, 361
organ, stimulus from, 399
processes, 416
reaction, 299
receptors, 298
system, 346
Vishnu, the Creator, 479
Vision, axis of, 409
Visual violet, 412
Vitalism, 96
Vitamin A, 144
where found, 143
Vitamin, antineuritic, 142, 143
antirachitic, 142, 143, 144
antiscorbutic, 142, 144
Vitamin B, 144
Vitamin C, 144
Vitamin D, 144
Vitamin X, 144
Vitamins, 142
Viviparous animals, 73
Vocal cords, development, 20
mechanism, 374
Voice, first, 20
Volcanoes, use of, 82
Volvox, colonies of, 105, 106
hermaphroditic, 106
unisexual, 106
Walking, 35
Wallace, 101
Walter, formulation of Mendel's law,
114
Washburn's Animal Mind, 270
Water, a solvent, 87, 88
amount in human body, 137
importance of, 136
behavior of, 87
chemical reactions in, 88
on earth, 81, 82
per cent in body, 87
excretions of, 88
Water-soluble B, 143
Watson, Dr. John B., viii
on light, 293
on love, 433
on nerve system, 333
on thinking, 383
quoted, 470, 471
Waves, Hertzian, 296, 298, 306
Weight, increase in body, 37
increases in from birth, 32, 33
Weismann, "biophores," 113
doctrine of continuity of germ-
plasm, 103
on death, 251
Wells, H. G., Outline of History, 40
Whales, adaptations of, 99
Wheelworms, 75
Whooping-cough, 199
INDEX
Wiggam, The New Decalogue of
Science, 119
Wirsung, duct of, 219
Wolfl&an body, cortex derived from,
209
Wolffian ducts, 17
changes in, 17
Women, change in after fifty, 38
heartbeats of, 166
Woodruff (quoted), 107
study of Paramecium, 98
World War, 141, 143, 144
Wrist, joint of, 67
turtles, 67
Yaws, cure for, 200
Youth, heartbeats of, 166
Zone, erogenous, 432, 439, 440
Zymase, 147
Zymogen, activator of enzymes,
Zymogenic bacteria, 195
512
Date Due
STEACi:
: 0.&TgJ
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